$es 2011 Q4 10-K

Concept	2011 Q4	2010 Q4	2010 Q3
Revenue	$1.068B	$1.204B	$1.243B
YoY Change	-11.3%	-8.45%	-4.82%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$79.40M	$72.00M	$181.7M
YoY Change	10.28%	-7.46%	135.97%
% of Gross Profit
Operating Expenses	$883.2M	$1.009B	$1.044B
YoY Change	-12.44%	-10.18%	-8.74%
Operating Profit	$184.9M	$195.3M	$199.6M
YoY Change	-5.33%
Interest Expense	-$65.70M	-$25.10M	$65.90M
YoY Change	161.75%	-61.09%	-203.61%
% of Operating Profit	-35.53%	-12.85%	33.02%
Other Income/Expense, Net	$8.600M	$10.30M	$10.12M
YoY Change	-16.5%	27.16%	189.09%
Pretax Income	$127.8M	$180.5M	$143.9M
YoY Change	-29.2%	32.72%	40.48%
Income Tax	$13.00M	$49.30M	$41.92M
% Of Pretax Income	10.17%	27.31%	29.14%
Net Earnings	$114.8M	$131.3M	$101.9M
YoY Change	-12.57%	52.5%	53.93%
Net Earnings / Revenue	10.75%	10.9%	8.2%
Basic Earnings Per Share			$0.57
Diluted Earnings Per Share	$644.6K	$740.0K	$0.57
COMMON SHARES
Basic Shares Outstanding	177.0M shares		176.8M shares
Diluted Shares Outstanding			177.0M shares

Concept	2011 Q4	2010 Q4	2010 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$78.00M	$102.0M	$121.0M
YoY Change	-23.53%	9.68%	-61.34%
Cash & Equivalents	$7.000M	$23.00M	$41.00M
Short-Term Investments	$71.00M	$78.00M	$80.00M
Other Short-Term Assets	$112.6M	$100.4M	$342.0M
YoY Change	12.14%	-71.87%	16.33%
Inventory	$249.0M	$244.0M	$247.0M
Prepaid Expenses
Receivables	$488.0M	$523.6M	$526.0M
Other Receivables	$0.00	$89.00M	$0.00
Total Short-Term Assets	$1.357B	$1.507B	$1.236B
YoY Change	-9.92%	18.85%	-16.49%
LONG-TERM ASSETS
Property, Plant & Equipment	$10.40B	$9.568B	$9.318B
YoY Change	8.73%	8.24%	8.06%
Goodwill	$300.0M	$287.6M
YoY Change	4.31%
Intangibles
YoY Change
Long-Term Investments	$2.100M	$2.000M	$46.00M
YoY Change	5.0%	-96.36%	-16.36%
Other Assets	$172.6M	$179.3M	$3.410B
YoY Change	-3.74%	-95.03%	-4.24%
Total Long-Term Assets	$3.887B	$3.398B	$13.06B
YoY Change	14.38%	-73.43%	4.28%
TOTAL ASSETS
Total Short-Term Assets	$1.357B	$1.507B	$1.236B
Total Long-Term Assets	$3.887B	$3.398B	$13.06B
Total Assets	$15.65B	$14.47B	$14.30B
YoY Change	8.12%	2.95%	2.08%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$633.3M	$417.3M	$451.0M
YoY Change	51.76%	-17.04%	10.0%
Accrued Expenses		$75.00M	$108.0M
YoY Change		-10.71%	21.35%
Deferred Revenue
YoY Change
Short-Term Debt	$317.0M	$267.0M	$156.0M
YoY Change	18.73%	167.0%	-52.0%
Long-Term Debt Due	$331.6M	$66.29M	$66.00M
YoY Change	400.23%	0.43%	0.0%
Total Short-Term Liabilities	$1.948B	$1.345B	$1.057B
YoY Change	44.79%	37.4%	-11.55%
LONG-TERM LIABILITIES
Long-Term Debt	$4.615B	$4.633B	$4.883B
YoY Change	-0.39%	-6.12%	0.72%
Other Long-Term Liabilities	$420.0M	$447.5M	$2.971B
YoY Change	-6.14%	-85.42%	0.64%
Total Long-Term Liabilities	$4.840B	$4.384B	$7.854B
YoY Change	10.41%	-45.23%	0.69%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.948B	$1.345B	$1.057B
Total Long-Term Liabilities	$4.840B	$4.384B	$7.854B
Total Liabilities	$6.788B	$5.729B	$10.46B
YoY Change	18.48%	-44.72%	0.98%
SHAREHOLDERS EQUITY
Retained Earnings	$1.652B	$1.453B
YoY Change	13.7%
Common Stock	$980.3M	$978.9M
YoY Change	0.14%
Preferred Stock
YoY Change
Treasury Stock (at cost)	-$346.7M	-$354.7M
YoY Change	-2.27%
Treasury Stock Shares	18.89M shares	19.33M shares
Shareholders Equity	$4.013B	$3.811B	$3.839B
YoY Change
Total Liabilities & Shareholders Equity	$15.65B	$14.47B	$14.30B
YoY Change	8.12%	2.95%	2.08%

Concept	2011 Q4	2010 Q4	2010 Q3
OPERATING ACTIVITIES
Net Income	$114.8M	$131.3M	$101.9M
YoY Change	-12.57%	52.5%	53.93%
Depreciation, Depletion And Amortization	$79.40M	$72.00M	$181.7M
YoY Change	10.28%	-7.46%	135.97%
Cash From Operating Activities	$82.00M	$249.9M	$309.8M
YoY Change	-67.19%	9.61%	22.55%
INVESTING ACTIVITIES
Capital Expenditures	-$327.6M	-$276.9M	-$235.2M
YoY Change	18.31%	1.17%	10.16%
Acquisitions
YoY Change
Other Investing Activities	$18.90M	$8.700M	-$6.700M
YoY Change	117.24%	180.65%	-578.57%
Cash From Investing Activities	-$308.7M	-$268.2M	-$241.9M
YoY Change	15.1%	-0.92%	14.05%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	216.7M	600.0K	-115.6M
YoY Change	36016.67%	-100.33%	-57.62%
NET CHANGE
Cash From Operating Activities	82.00M	249.9M	309.8M
Cash From Investing Activities	-308.7M	-268.2M	-241.9M
Cash From Financing Activities	216.7M	600.0K	-115.6M
Net Change In Cash	-10.00M	-17.70M	-47.70M
YoY Change	-43.5%	-92.03%	-79.45%
FREE CASH FLOW
Cash From Operating Activities	$82.00M	$249.9M	$309.8M
Capital Expenditures	-$327.6M	-$276.9M	-$235.2M
Free Cash Flow	$409.6M	$526.8M	$545.0M
YoY Change	-22.25%	5.0%	16.88%

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2011Q4	us-gaap	Capital Leases Future Minimum Payments Due Current CapitalLeasesFutureMinimumPaymentsDueCurrent	3000000	USD
CY2011Q4	us-gaap	Cash Cash	6559000	USD
CY2011Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	488002000	USD
CY2011Q4	us-gaap	Costs In Excess Of Billings On Uncompleted Contracts Or Programs Expected To Be Collected Within One Year CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear	175207000	USD
CY2011Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	4931000	USD
CY2011Q4	us-gaap	Energy Related Inventory EnergyRelatedInventory	248958000	USD
CY2011Q4	us-gaap	Marketable Securities Current MarketableSecuritiesCurrent	70970000	USD
CY2011Q4	us-gaap	Other Assets Current OtherAssetsCurrent	107701000	USD
CY2011Q4	us-gaap	Assets Current AssetsCurrent	1357472000	USD
CY2010Q4	us-gaap	Cash Cash	23395000	USD
CY2010Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	523644000	USD
CY2010Q4	us-gaap	Costs In Excess Of Billings On Uncompleted Contracts Or Programs Expected To Be Collected Within One Year CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear	208834000	USD
CY2010Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	89638000	USD
CY2010Q4	us-gaap	Energy Related Inventory EnergyRelatedInventory	244043000	USD
CY2010Q4	us-gaap	Marketable Securities Current MarketableSecuritiesCurrent	78306000	USD
CY2010Q4	us-gaap	Other Assets Current OtherAssetsCurrent	100441000	USD
CY2010Q4	us-gaap	Assets Current AssetsCurrent	1507000000	USD
CY2011Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	3267710000	USD
CY2010Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	2756580000	USD
CY2011Q4	us-gaap	Goodwill Goodwill	287591000	USD
CY2010Q4	us-gaap	Goodwill Goodwill	287591000	USD
CY2011Q4	us-gaap	Marketable Securities Noncurrent MarketableSecuritiesNoncurrent	60311000	USD
CY2010Q4	us-gaap	Marketable Securities Noncurrent MarketableSecuritiesNoncurrent	51201000	USD
CY2011Q4	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	98357000	USD
CY2010Q4	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	123242000	USD
CY2011Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	172560000	USD
CY2010Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	179261000	USD
CY2011Q4	us-gaap	Assets Noncurrent AssetsNoncurrent	3886529000	USD
CY2010Q4	us-gaap	Assets Noncurrent AssetsNoncurrent	3397875000	USD
CY2011Q4	us-gaap	Assets Assets	15647066000	USD
CY2010Q4	us-gaap	Assets Assets	14472601000	USD
CY2011Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	255144000	USD
CY2010Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	238699000	USD
CY2011Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	10403065000	USD
CY2010Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	9567726000	USD
CY2011Q4	us-gaap	Notes Payable To Bank Current NotesPayableToBankCurrent	317000000	USD
CY2010Q4	us-gaap	Notes Payable To Bank Current NotesPayableToBankCurrent	267000000	USD
CY2011Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	331582000	USD
CY2010Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	66286000	USD
CY2011Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	633282000	USD
CY2010Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	417285000	USD
CY2011Q4	us-gaap	Accounts Payable Other Current AccountsPayableOtherCurrent	75068000	USD
CY2010Q4	us-gaap	Accounts Payable Other Current AccountsPayableOtherCurrent	74659000	USD
CY2011Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	69592000	USD
CY2010Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	107067000	USD
CY2011Q4	us-gaap	Interest Payable Current InterestPayableCurrent	69198000	USD
CY2010Q4	us-gaap	Interest Payable Current InterestPayableCurrent	74740000	USD
CY2010	us-gaap	Revenues Revenues	4898167000	USD
CY2011Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	107558000	USD
CY2010Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	71501000	USD
CY2011Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	176558000	USD
CY2010Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	167206000	USD
CY2011Q4	us-gaap	Liabilities Current LiabilitiesCurrent	1947682000	USD
CY2010Q4	us-gaap	Liabilities Current LiabilitiesCurrent	1345147000	USD
CY2011Q4	us-gaap	Secured Long Term Debt SecuredLongTermDebt	112260000	USD
CY2010Q4	us-gaap	Secured Long Term Debt SecuredLongTermDebt	181572000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	1868316000	USD
CY2010Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	1636750000	USD
CY2011Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	266145000	USD
CY2010Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	339655000	USD
CY2011Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	959876000	USD
CY2010Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	909668000	USD
CY2011Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	1326037000	USD
CY2010Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	1050614000	USD
CY2011Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	420011000	USD
CY2010Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	447496000	USD
CY2011Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	4840385000	USD
CY2010Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	4384183000	USD
CY2011Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	4614913000	USD
CY2010Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	4632866000	USD
CY2011Q4	us-gaap	Temporary Equity Carrying Amount TemporaryEquityCarryingAmount	116200000	USD
CY2010Q4	us-gaap	Temporary Equity Carrying Amount TemporaryEquityCarryingAmount	116200000	USD
CY2011Q4	us-gaap	Common Stock Value CommonStockValue	980264000	USD
CY2010Q4	us-gaap	Common Stock Value CommonStockValue	978909000	USD
CY2011Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	1797884000	USD
CY2010Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	1777592000	USD
CY2011Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1651875000	USD
CY2010Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1452777000	USD
CY2011Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	70686000	USD
CY2010Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	43370000	USD
CY2011Q4	us-gaap	Treasury Stock Value TreasuryStockValue	-346667000	USD
CY2010Q4	us-gaap	Treasury Stock Value TreasuryStockValue	-354732000	USD
CY2011Q4	us-gaap	Stockholders Equity StockholdersEquity	4012670000	USD
CY2010Q4	us-gaap	Stockholders Equity StockholdersEquity	3811176000	USD
CY2011Q4	us-gaap	Minority Interest MinorityInterest	2956000	USD
CY2010Q4	us-gaap	Minority Interest MinorityInterest	1457000	USD
CY2011Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4015626000	USD
CY2010Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3812633000	USD
CY2011Q4	us-gaap	Capitalization Longterm Debt And Equity CapitalizationLongtermDebtAndEquity	8746739000	USD
CY2010Q4	us-gaap	Capitalization Longterm Debt And Equity CapitalizationLongtermDebtAndEquity	8561699000	USD
CY2011Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	15647066000	USD
CY2010Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	14472601000	USD
CY2011Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	167844000	USD
CY2010Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	99403000	USD
CY2011	us-gaap	Revenues Revenues	4465657000	USD
CY2009	us-gaap	Revenues Revenues	5439430000	USD
CY2011	us-gaap	Cost Of Purchased Power CostOfPurchasedPower	1580683000	USD
CY2010	us-gaap	Cost Of Purchased Power CostOfPurchasedPower	1985634000	USD
CY2009	us-gaap	Cost Of Purchased Power CostOfPurchasedPower	2629619000	USD
CY2011	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	1026192000	USD
CY2010	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	958417000	USD
CY2009	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	1001190000	USD
CY2011	us-gaap	Maintenance Costs MaintenanceCosts	271779000	USD
CY2010	us-gaap	Maintenance Costs MaintenanceCosts	210283000	USD
CY2009	us-gaap	Maintenance Costs MaintenanceCosts	234173000	USD
CY2011	us-gaap	Depreciation Depreciation	302192000	USD
CY2010	us-gaap	Depreciation Depreciation	300737000	USD
CY2009	us-gaap	Depreciation Depreciation	309618000	USD
CY2011	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	97113000	USD
CY2010	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	95593000	USD
CY2009	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	13315000	USD
CY2011	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	69912000	USD
CY2010	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	232871000	USD
CY2009	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	217941000	USD
CY2011	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	323610000	USD
CY2010	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	314741000	USD
CY2009	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	282199000	USD
CY2011	us-gaap	Operating Expenses OperatingExpenses	3671481000	USD
CY2010	us-gaap	Operating Expenses OperatingExpenses	4098276000	USD
CY2009	us-gaap	Operating Expenses OperatingExpenses	4688055000	USD
CY2011	us-gaap	Operating Income Loss OperatingIncomeLoss	794176000	USD
CY2010	us-gaap	Operating Income Loss OperatingIncomeLoss	799891000	USD
CY2009	us-gaap	Operating Income Loss OperatingIncomeLoss	751375000	USD
CY2011	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	231630000	USD
CY2010	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	231089000	USD
CY2009	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	224712000	USD
CY2011	us-gaap	Interest Expense Other Long Term Debt InterestExpenseOtherLongTermDebt	8611000	USD
CY2010	us-gaap	Interest Expense Other Long Term Debt InterestExpenseOtherLongTermDebt	20573000	USD
CY2009	us-gaap	Interest Expense Other Long Term Debt InterestExpenseOtherLongTermDebt	36524000	USD
CY2011	us-gaap	Interest Expense Other InterestExpenseOther	10184000	USD
CY2010	us-gaap	Interest Expense Other InterestExpenseOther	-14371000	USD
CY2009	us-gaap	Interest Expense Other InterestExpenseOther	12401000	USD
CY2011	us-gaap	Interest Expense InterestExpense	250425000	USD
CY2010	us-gaap	Interest Expense InterestExpense	237291000	USD
CY2009	us-gaap	Interest Expense InterestExpense	273637000	USD
CY2011	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	27715000	USD
CY2010	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	41916000	USD
CY2009	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	37801000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	571466000	USD
CY2010	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	604516000	USD
CY2009	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	515539000	USD
CY2011	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	170953000	USD
CY2010	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	210409000	USD
CY2009	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	179947000	USD
CY2011	us-gaap	Net Income Loss NetIncomeLoss	400513000	USD
CY2010	us-gaap	Net Income Loss NetIncomeLoss	394107000	USD
CY2009	us-gaap	Net Income Loss NetIncomeLoss	335592000	USD
CY2011	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	5820000	USD
CY2010	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	6158000	USD
CY2009	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	5559000	USD
CY2011	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	394693000	USD
CY2010	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	387949000	USD
CY2009	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	330033000	USD
CY2011	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	177804568	shares
CY2010	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	176885387	shares
CY2009	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	172717246	shares
CY2011	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	177410167	shares
CY2010	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	176636086	shares
CY2009	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172567928	shares
CY2011	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Period Increase Decrease OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPeriodIncreaseDecrease	-14177000	USD
CY2010	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Period Increase Decrease OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPeriodIncreaseDecrease	200000	USD
CY2011	us-gaap	Other Comprehensive Income Available For Sale Securities Adjustment Net Of Tax Period Increase Decrease OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecrease	506000	USD
CY2010	us-gaap	Other Comprehensive Income Available For Sale Securities Adjustment Net Of Tax Period Increase Decrease OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecrease	402000	USD
CY2009	us-gaap	Other Comprehensive Income Available For Sale Securities Adjustment Net Of Tax Period Increase Decrease OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecrease	-976000	USD
CY2011	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Period Increase Decrease OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecrease	-13645000	USD
CY2010	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Period Increase Decrease OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecrease	-505000	USD
CY2009	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Period Increase Decrease OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecrease	-5426000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Net Of Tax Period Increase Decrease OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease	-27316000	USD
CY2010	us-gaap	Other Comprehensive Income Loss Net Of Tax Period Increase Decrease OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease	97000	USD
CY2009	us-gaap	Other Comprehensive Income Loss Net Of Tax Period Increase Decrease OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease	-6202000	USD
CY2011	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	5820000	USD
CY2010	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	6158000	USD
CY2009	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	5559000	USD
CY2011	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	367377000	USD
CY2010	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	388046000	USD
CY2009	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	323831000	USD
CY2009	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Period Increase Decrease OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPeriodIncreaseDecrease	200000	USD
CY2011	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	16420000	USD
CY2009	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	53947000	USD
CY2011	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	196761000	USD
CY2009	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	125890000	USD
CY2011	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	133000000	USD
CY2011	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	76896000	USD
CY2009	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	-37868000	USD
CY2009	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	58732000	USD
CY2011	us-gaap	Increase Decrease In Fair Value Of Unhedged Derivative Instruments IncreaseDecreaseInFairValueOfUnhedgedDerivativeInstruments	35441000	USD
CY2009	us-gaap	Increase Decrease In Fair Value Of Unhedged Derivative Instruments IncreaseDecreaseInFairValueOfUnhedgedDerivativeInstruments	18798000	USD
CY2011	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-29751000	USD
CY2009	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-26003000	USD
CY2011	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-17570000	USD
CY2009	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-91081000	USD
CY2011	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	11033000	USD
CY2009	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-25957000	USD
CY2011	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	-49642000	USD
CY2009	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	-16194000	USD
CY2011	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	18916000	USD
CY2009	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-208180000	USD
CY2011	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-12569000	USD
CY2009	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	6876000	USD
CY2011	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	970386000	USD
CY2009	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	989118000	USD
CY2011	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1076730000	USD
CY2009	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	908146000	USD
CY2011	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	149441000	USD
CY2009	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	208947000	USD
CY2011	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	151972000	USD
CY2011	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-13833000	USD
CY2011	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1018587000	USD
CY2009	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	162381000	USD
CY2009	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	5559000	USD
CY2011	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	69312000	USD
CY2011	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-7123000	USD
CY2011	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	31365000	USD
CY2011	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-16836000	USD
CY2011	us-gaap	Pension Contributions PensionContributions	191101000	USD
CY2009	us-gaap	Pension Contributions PensionContributions	37160000	USD
CY2011	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	46841000	USD
CY2009	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2011	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	369586000	USD
CY2010	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	31352000	USD
CY2010	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	210939000	USD
CY2010	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	103861000	USD
CY2010	us-gaap	Pension Contributions PensionContributions	90633000	USD
CY2010	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	-20750000	USD
CY2010	us-gaap	Increase Decrease In Fair Value Of Unhedged Derivative Instruments IncreaseDecreaseInFairValueOfUnhedgedDerivativeInstruments	11812000	USD
CY2010	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-72151000	USD
CY2010	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	51285000	USD
CY2010	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-38126000	USD
CY2010	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	82103000	USD
CY2010	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-44355000	USD
CY2010	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-17466000	USD
CY2010	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1093463000	USD
CY2010	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	954472000	USD
CY2010	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	174865000	USD
CY2010	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	177204000	USD
CY2010	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2010	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	1157000	USD
CY2010	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-957968000	USD
CY2009	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-518584000	USD
CY2009	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	462000000	USD
CY2010	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	260864000	USD
CY2010	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	4286000	USD
CY2010	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	512000	USD
CY2010	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-139052000	USD
CY2010	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-3557000	USD
CY2009	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	211243000	USD
CY2009	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-7963000	USD
CY2009	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-902479000	USD
CY2008Q4	us-gaap	Cash Cash	89816000	USD
CY2009Q4	us-gaap	Cash Cash	26952000	USD
CY2011	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	0	USD
CY2011	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	194555000	USD
CY2011	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	5559000	USD
CY2011	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	50000000	USD
CY2011	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	627500000	USD
CY2010	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	0	USD
CY2010	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	180542000	USD
CY2010	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	5559000	USD
CY2010	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	166687000	USD
CY2010	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	145000000	USD
CY2009	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	383295000	USD
CY2009	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	54286000	USD
CY2009	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	244075000	USD
CY2009	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-9913000	USD
CY2009	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-149503000	USD
CY2009	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-62864000	USD
CY2011Q4	nu	Exchange Ratio For Common Shares Converted As A Result Of Merger ExchangeRatioForCommonSharesConvertedAsAResultOfMerger	1.312	pure
CY2011Q4	nu	Nu Ownership Post Merger NuOwnershipPostMerger	0.56	pure
CY2011Q4	nu	Common Shares Issued As A Result Of Merger CommonSharesIssuedAsAResultOfMerger	137000000	shares
CY2011Q4	nu	Nstar Ownership Post Merger NstarOwnershipPostMerger	0.44	pure
CY2010Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	39800000	USD
CY2011Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	34900000	USD
CY2010Q4	nu	Rate Reduction Bond Deposits RateReductionBondDeposits	53100000	USD
CY2011Q4	nu	Rate Reduction Bond Deposits RateReductionBondDeposits	29500000	USD
CY2011	nu	Other Deposits OtherDeposits	17700000	USD
CY2010	nu	Other Deposits OtherDeposits	29900000	USD
CY2011Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	17900000	USD
CY2010Q4	us-gaap	Equity Method Investments EquityMethodInvestments	2000000	USD
CY2011Q4	us-gaap	Equity Method Investments EquityMethodInvestments	2100000	USD
CY2011Q4	nu	Schedule21 Nu Wholesale Transmission Revenue Rates Overrecoveryunderrecovery Position Schedule21NuWholesaleTransmissionRevenueRatesOverrecoveryunderrecoveryPosition	31400000	USD
CY2011Q4	nu	Schedule Of Fuel Costs ScheduleOfFuelCosts	<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 10px"><td style="width: 190px; text-align:left;border-color:#000000;min-width:190px;"> </td><td colspan="8" style="width: 290px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:290px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">For the Years Ended December 31,</font></td></tr><tr style="height: 10px"><td style="width: 190px; text-align:left;border-color:#000000;min-width:190px;"><font style="FONT-STYLE: italic;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: left;">(Millions of Dollars)</font></td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">2011</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">2010</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">2009</font></td></tr><tr style="height: 10px"><td style="width: 190px; text-align:left;border-color:#000000;min-width:190px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">NU</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 307.9</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 391.6</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 401.7</font></td></tr><tr style="height: 9px"><td style="width: 190px; text-align:left;border-color:#000000;min-width:190px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">PSNH</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 115.9</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 184.3</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 174.1</font></td></tr><tr style="height: 10px"><td style="width: 190px; text-align:left;border-color:#000000;min-width:190px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Yankee Gas</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 191.3</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 206.4</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 226.1</font></td></tr></table></div>
CY2011	nu	Fuel Power Costs FuelPowerCosts	307900000	USD
CY2010	nu	Fuel Power Costs FuelPowerCosts	391600000	USD
CY2009	nu	Fuel Power Costs FuelPowerCosts	401700000	USD
CY2011	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	-11800000	USD
CY2011	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	22500000	USD
CY2011	nu	Public Utilities Allowance For Funds Used During Construction Capitalized Total PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedTotal	34300000	USD
CY2010	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	-10200000	USD
CY2010	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	16700000	USD
CY2010	nu	Public Utilities Allowance For Funds Used During Construction Capitalized Total PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedTotal	26900000	USD
CY2009	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	-5900000	USD
CY2009	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	9400000	USD
CY2009	nu	Public Utilities Allowance For Funds Used During Construction Capitalized Total PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedTotal	15300000	USD
CY2011	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.073	pure
CY2010	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.071	pure
CY2009	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.061	pure
CY2011	us-gaap	Excise And Sales Taxes ExciseAndSalesTaxes	137800000	USD
CY2010	us-gaap	Excise And Sales Taxes ExciseAndSalesTaxes	143700000	USD
CY2009	us-gaap	Excise And Sales Taxes ExciseAndSalesTaxes	135600000	USD
CY2011	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	168500000	USD
CY2010	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	127900000	USD
CY2009	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	125500000	USD
CY2011	us-gaap	Interest Paid Net InterestPaidNet	256300000	USD
CY2010	us-gaap	Interest Paid Net InterestPaidNet	258300000	USD
CY2009	us-gaap	Interest Paid Net InterestPaidNet	263800000	USD
CY2009	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	35100000	USD
CY2010	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	84500000	USD
CY2011	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-76600000	USD
CY2010	nu	Contributions To Nu Foundation ContributionsToNuFoundation	2000000	USD
CY2011Q4	us-gaap	Regulatory Assets RegulatoryAssets	3522800000	USD
CY2010Q4	us-gaap	Regulatory Assets RegulatoryAssets	2995300000	USD
CY2011	us-gaap	Description Of Regulatory Costs Not Yet Approved DescriptionOfRegulatoryCostsNotYetApproved	Additionally, the Regulated companies had $32.4 million ($5 million for CL&P, $22.4 million for PSNH, and $1.6 million for WMECO) and $37.5 million ($0.6 million for CL&P, $26.5 million for PSNH, and $1.9 million for WMECO) of regulatory costs as of December 31, 2011 and 2010, respectively, which were included in Other Long-Term Assets on the accompanying consolidated balance sheets. These amounts represent incurred costs that have not yet been approved for recovery by the applicable regulatory agency. Management believes these costs are probable of recovery in future cost-of-service regulated rates. Of the total December 31, 2011 amount, $21.7 million for PSNH related to costs incurred for Tropical Storm Irene and the October snowstorm restorations that met the NHPUC criteria for cost deferral. Refer to the "Storm Cost Deferrals" section below for further discussion.
CY2011	nu	Description Of Regulatory Costs Recently Approved DescriptionOfRegulatoryCostsRecentlyApproved	The December 31, 2010 balance of regulatory costs included in Other Long-Term Assets at PSNH included costs incurred for the February 2010 wind storm restorations that met the NHPUC specified criteria for cost deferral and certain costs related to previously recognized lost tax benefits as a result of a provision in the 2010 Healthcare Act that eliminated the tax deductibility of actuarially equivalent Medicare Part D benefits for retirees. During June 2011, the NHPUC approved these costs for recovery, with a return on the storm costs, and PSNH recorded a regulatory asset of $10.9 million related to the wind storm restoration costs and $7.2 million for the recovery of the lost tax benefits. On July 28, 2010, PURA allowed the creation by CL&P of a regulatory asset for the recovery of lost tax benefits as a result of the 2010 Healthcare Act, subject to review in its next rate case. On January 31, 2011, the DPU allowed the creation by WMECO of a regulatory asset as a result of the 2010 Healthcare Act. NU has concluded that the costs associated with these lost tax benefits are probable of recovery and as of December 31, 2011, $32.2 million ($18.9 million for CL&P, $6.6 million for PSNH, $3.2 million for WMECO and $3.5 million for Yankee Gas) are included in Other Regulatory Assets in the table above. These assets are not earning a return. PSNH and WMECO's costs are being recovered over a period of 5 to 7 years. For further information regarding the 2010 Healthcare Act, see Note 11, "Income Taxes," to the consolidated financial statements.
CY2011	nu	Description Of Accumulated Equity Return DescriptionOfAccumulatedEquityReturn	For rate-making purposes, the Regulated companies recover the cost of allowed equity return on certain regulatory assets. This cost, which is not recorded on the accompanying consolidated balance sheets, totaled $3.5 million and $6.1 million for CL&P and $7.6 million and $0.5 million for PSNH as of December 31, 2011 and 2010, respectively. These costs will be recovered in rates.
CY2011	us-gaap	Description Of Regulatory Assets And Liabilities DescriptionOfRegulatoryAssetsAndLiabilities	Deferred Benefit Costs: NU's Pension, SERP and PBOP Plans are accounted for in accordance with accounting guidance on defined benefit pension and other postretirement plans. Under this accounting guidance, the funded status of pension and other postretirement plans is recorded with an offset to Accumulated Other Comprehensive Income/(Loss) and is remeasured annually. However, because the Regulated companies are rate-regulated on a cost-of-service basis, offsets were recorded as regulatory assets as of December 31, 2011 and 2010 as these amounts have been, and continue to be, recoverable in cost-of-service regulated rates. Regulatory accounting was also applied to the portions of the NUSCO costs that support the Regulated companies, as these amounts are also recoverable. The deferred benefit costs of CL&P and PSNH are not in rate base. WMECO's deferred benefit costs are earning an equity return at the same rate as the assets included in rate base. Pension and PBOP costs are expected to be amortized into expense over the average future employee service period of approximately 10 and 9 years, respectively. Regulatory Assets Offsetting Derivative Liabilities: The regulatory assets offsetting derivative liabilities relate to the fair value of contracts used to purchase power and other related contracts that will be collected from customers in the future. Included in these amounts are derivative liabilities relating to CL&P's capacity contracts, referred to as CfDs. See Note 4, "Derivative Instruments," to the consolidated financial statements for further information.  These assets are excluded from rate base and are being recovered as the actual settlement occurs over the duration of the contracts. Securitized Assets: In April 2001, PSNH issued RRBs in the amount of $525 million. PSNH used the majority of the proceeds from that issuance to buydown its power contracts with an affiliate, North Atlantic Energy Corporation. In May 2001, WMECO issued $155 million in RRBs and used the majority of the proceeds from that issuance to buyout an IPP contract. These assets are not earning an equity return and are being recovered over the amortization period of their associated RRBs. PSNH RRBs are scheduled to fully amortize by May 1, 2013 and WMECO RRBs are scheduled to fully amortize by June 1, 2013. Income Taxes, Net: The tax effect of temporary differences (differences between the periods in which transactions affect income in the financial statements and the periods in which they affect the determination of taxable income, including those differences relating to uncertain tax positions) is accounted for in accordance with the rate-making treatment of the applicable regulatory commissions and accounting guidance for income taxes. Differences in income taxes between the accounting guidance and the rate-making treatment of the applicable regulatory commissions are recorded as regulatory assets. These assets are excluded from rate base. For further information regarding income taxes, see Note 11, "Income Taxes," to the consolidated financial statements. Unrecovered Contractual Obligations: Under the terms of contracts with CYAPC, YAEC and MYAPC, CL&P, PSNH and WMECO are responsible for their proportionate share of the remaining costs of the nuclear facilities, including decommissioning. A portion of these amounts was recorded as unrecovered contractual obligations regulatory assets. These obligations for CL&P are earning a return and are being recovered through the CTA. Amounts for WMECO are being recovered without a return and are anticipated to be recovered by 2013, the scheduled completion date of stranded cost recovery. Amounts for PSNH were fully recovered by 2006. Regulatory Tracker Deferrals: Regulatory tracker deferrals are approved rate mechanisms that allow utilities to recover costs in specific business segments through reconcilable tracking mechanisms that are reviewed at least annually by the applicable regulatory commission. The reconciliation process produces deferrals for future recovery or refund, which can be either under or over-collections to be included in future customer rates each year. Regulatory tracker deferrals are recorded as regulatory assets if costs are in excess of collections from customers and are recorded as regulatory liabilities if collections from customers are in excess of costs. All material regulatory tracker deferrals that are in a regulatory asset position are earning some form of return. The following regulatory tracker deferrals were recorded as either regulatory assets or liabilities as of December 31, 2011 and 2010: CL&P Reconciliation Mechanisms: The PURA has established several reconciliation mechanisms, which allow CL&P to recover costs associated with the procurement of energy for SS and LRS, congestion and other costs associated with power market rules approved by the FERC or as approved by the PURA, C&LM programs, the retail transmission of energy, certain regulatory and energy public policy costs, such as hardship protection costs and transition period property taxes, and stranded costs, such as the amortization of regulatory assets and IPP over market costs. As part of the CTA mechanism reconciliation process, CL&P has also established an obligation to refund the variable incentive portion of its transition service procurement fee, which totaled $26.3 million and $24.7 million as of December 31, 2011 and 2010, respectively, and was recorded as a regulatory liability. PSNH Reconciliation Mechanisms: The NHPUC permits PSNH to recover the costs of providing generation, restructuring costs as a result of deregulation, the retail transmission of energy, and the cost of C&LM programs through various reconciliation mechanisms. WMECO Reconciliation Mechanisms: The DPU has approved a number of individual cost and revenue requirement recovery mechanisms. These mechanisms recover costs associated with providing energy, retail transmission of energy, administrative costs to procure energy, bad debt costs associated with providing energy, company investments in renewable energy, such as solar, and credits given to customers who generate renewable energy. There is also a mechanism for the recovery of stranded generation costs. Additionally, the DPU has provided cost and revenue requirement recovery mechanisms for certain operating expenses. These individual mechanisms include recovery of pension and PBOP costs, certain state government regulatory review, energy efficiency programs, customer arrearage forgiveness programs and low income customer discounts. In the January 31, 2011 rate case, WMECO received approval for a revenue decoupling reconciliation mechanism, which provides assurance that WMECO will recover a DPU pre-established level of baseline distribution delivery service revenue to manage all other distribution operating expenses and earn a level of return on its capital investment. Storm Cost Deferrals: The storm cost deferrals relate to costs incurred at CL&P, PSNH and WMECO for restorations that met regulatory agency specified criteria for cost deferral. On June 1, 2011, a series of severe thunderstorms with high winds, including tornadoes, struck portions of WMECO’s service territory. On June 9, 2011, another series of severe thunderstorms with high winds struck CL&P, PSNH and WMECO's service territories. The cost of restoration that was deferred for future recovery from customers and recorded as a regulatory asset as of December 31, 2011 for CL&P and WMECO totaled $11 million and $3.3 million, respectively. On August 28, 2011, Tropical Storm Irene caused extensive damage to NU’s distribution system. The estimated cost of restoration that was deferred for future recovery from customers and recorded as a regulatory asset as of December 31, 2011 for CL&P and WMECO totaled $105.6 million and $3.2 million, respectively. PSNH recorded $7 million in Other Long-Term Assets as previously described. On October 29, 2011, an unprecedented storm inundated NU’s service territory with heavy snow causing significant damage to NU’s distribution and transmission systems. In terms of customer outages, this was the most severe storm in CL&P’s history, surpassing Tropical Storm Irene; the third most severe in PSNH’s history and the most severe in WMECO's history. The estimated cost of restoration that was deferred for future recovery from customers and recorded as a regulatory asset as of December 31, 2011 for CL&P and WMECO totaled $157.7 million and $23.5 million, respectively. PSNH recorded $14.7 million in Other Long-Term Assets as previously described. The estimated cost of restoration is subject to change as additional cost information becomes available. Management believes its response to the storm damage was prudent and therefore believes it is probable that CL&P, PSNH and WMECO will be allowed to recover these deferred storm costs. CL&P, PSNH and WMECO will seek recovery of these estimated deferred storm costs through the appropriate regulatory recovery process. The PSNH deferral as of December 31, 2011 relates to remaining costs incurred for a major storm in December 2008 and the February 2010 wind storm restorations, both of which were approved for recovery and are included in rate base. WMECO's remaining storm deferral relates to 2008 and 2010 storm costs, which were approved for recovery and are earning a return. Asset Retirement Obligations: The costs associated with the depreciation of the Regulated companies' ARO assets and accretion of the ARO liabilities are recorded as regulatory assets in accordance with regulatory accounting guidance. For CL&P and WMECO, ARO assets, regulatory assets and liabilities offset and are excluded from rate base. PSNH's ARO assets, regulatory assets and liabilities are included in rate base. These costs are being recovered over the life of the underlying property, plant and equipment. Losses on Reacquired Debt: The regulatory asset relates to the losses associated with the reacquisition or redemption of long-term debt and are amortized over the life of the respective long-term debt issuance. These deferred losses are incorporated as part of debt costs included in the rate of return calculation. Deferred Environmental Remediation Costs: This regulatory asset relates to environmental remediation costs at PSNH of $9.7 million and Yankee Gas of $28.8 million. Both PSNH and Yankee Gas have regulatory rate recovery mechanisms for environmental costs and accordingly, offsets to environmental reserves were recorded as regulatory assets. Management continues to believe these costs are probable of recovery in future cost-of-service regulated rates. Deferred Operation and Maintenance Costs: This regulatory asset represents the deferral of maintenance expense in connection with the deferred recovery of revenue requirements for the period July 1, 2010 through December 31, 2010, as allowed by the PURA. CL&P is allowed to recover these costs from January 1, 2011 through June 30, 2012. Cost of Removal: NU's Regulated companies currently recover amounts in rates for future costs of removal of plant assets over the lives of the assets. These amounts are classified as Regulatory Liabilities on the accompanying consolidated balance sheets. Regulatory Liabilities Offsetting Derivative Assets: The regulatory liabilities offsetting derivative assets relate to the fair value of contracts used to purchase power and other related contracts that will benefit customers in the future. See Note 4, "Derivative Instruments," to the consolidated financial statements for further information. This liability is excluded from rate base and is refunded as the actual settlement occurs over the duration of the contracts. AFUDC Transmission Incentive: AFUDC was recorded on 100 percent of CL&P and WMECO's CWIP for their NEEWS projects through May 31, 2011, all of which was reserved as a regulatory liability to reflect rate base recovery for 100 percent of the CWIP as a result of FERC-approved transmission incentives. Effective June 1, 2011, FERC approved changes to the ISO-NE Tariff in order to include 100 percent of the NEEWS CWIP in regional rate base. As a result, CL&P and WMECO no longer record AFUDC on NEEWS CWIP. Overrecovered Spent Nuclear Fuel Costs and Contractual Obligations: CL&P and WMECO currently recover amounts in rates for costs of disposal of spent nuclear fuel and high-level radioactive waste for the period prior to the sale of their ownership shares in the Millstone nuclear power stations. Collections in excess of these costs are recorded as regulatory liabilities. CL&P has also established a regulatory liability for the overrecovery of its proportionate share of the remaining costs, including decommissioning, of the MYAPC nuclear facility. Wholesale Transmission Overcollections: CL&P, PSNH and WMECO's transmission rates recover total transmission revenue requirements, recovering all regional and local revenue requirements for providing transmission service. These rates provide for annual reconciliations to actual costs and the difference between billed and actual costs is deferred. Regulatory liabilities were recorded for collections in excess of costs. Pension Liability - Yankee Gas Acquisition: When Yankee Gas was acquired by NU, the pension liability was adjusted to fair value with an offset to the adjustment recorded as a regulatory liability, as approved by the PURA. The pension liability was approved for amortization over an approximate 13-year period beginning in 2002.
CY2011Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	433900000	USD
CY2010Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	439100000	USD
CY2011Q4	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	6540400000	USD
CY2011Q4	nu	Public Utilities Property Plant And Equipment Distribution Natural Gas PublicUtilitiesPropertyPlantAndEquipmentDistributionNaturalGas	1247600000	USD
CY2011Q4	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	3541900000	USD
CY2011Q4	us-gaap	Public Utilities Property Plant And Equipment Generation Or Processing PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing	1096000000	USD
CY2011Q4	nu	Public Utilities Property Plant And Equipment Electric And Natural Gas Utility Total PublicUtilitiesPropertyPlantAndEquipmentElectricAndNaturalGasUtilityTotal	12425900000	USD
CY2011Q4	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	305100000	USD
CY2011Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	12731000000	USD
CY2011Q4	nu	Electric And Natural Gas Utility Accumulated Depreciation ElectricAndNaturalGasUtilityAccumulatedDepreciation	3035500000	USD
CY2011Q4	nu	Other Accumulated Depreciation OtherAccumulatedDepreciation	120200000	USD
CY2011Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	3155700000	USD
CY2011Q4	nu	Property Plant And Equipment Net Excluding Construction Work In Progress PropertyPlantAndEquipmentNetExcludingConstructionWorkInProgress	9575300000	USD
CY2011Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	827800000	USD
CY2010Q4	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	6197200000	USD
CY2010Q4	nu	Public Utilities Property Plant And Equipment Distribution Natural Gas PublicUtilitiesPropertyPlantAndEquipmentDistributionNaturalGas	1126600000	USD
CY2010Q4	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	3378000000	USD
CY2010Q4	us-gaap	Public Utilities Property Plant And Equipment Generation Or Processing PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing	697100000	USD
CY2010Q4	nu	Public Utilities Property Plant And Equipment Electric And Natural Gas Utility Total PublicUtilitiesPropertyPlantAndEquipmentElectricAndNaturalGasUtilityTotal	11398900000	USD
CY2010Q4	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	305500000	USD
CY2010Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	11704400000	USD
CY2010Q4	nu	Electric And Natural Gas Utility Accumulated Depreciation ElectricAndNaturalGasUtilityAccumulatedDepreciation	2862300000	USD
CY2010Q4	nu	Other Accumulated Depreciation OtherAccumulatedDepreciation	119900000	USD
CY2010Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	2982200000	USD
CY2010Q4	nu	Property Plant And Equipment Net Excluding Construction Work In Progress PropertyPlantAndEquipmentNetExcludingConstructionWorkInProgress	8722200000	USD
CY2010Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	845500000	USD
CY2011Q4	nu	Advance Payments On Equipment Purchase Contracts AdvancePaymentsOnEquipmentPurchaseContracts	15200000	USD
CY2010Q4	nu	Advance Payments On Equipment Purchase Contracts AdvancePaymentsOnEquipmentPurchaseContracts	9300000	USD
CY2011	nu	Distribution Average Depreciable Lives DistributionAverageDepreciableLives	38.8	pure
CY2011	nu	Transmission Average Depreciable Lives TransmissionAverageDepreciableLives	41.2	pure
CY2011	nu	Generation Average Depreciable Lives GenerationAverageDepreciableLives	29.6	pure
CY2011	nu	Other Average Depreciable Lives OtherAverageDepreciableLives	17.7	pure
CY2011	nu	Schedule Of Plant Average Depreciable Lives ScheduleOfPlantAverageDepreciableLives	<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;"> </td><td colspan="11" style="width: 390px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:390px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Average Depreciable Life</font></td></tr><tr style="height: 10px"><td colspan="2" style="width: 120px; text-align:left;border-color:#000000;min-width:120px;"><font style="FONT-STYLE: italic;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: left;">(Years)</font></td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">NU</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">CL&P</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">PSNH</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">WMECO</font></td></tr><tr style="height: 10px"><td colspan="2" style="width: 120px; text-align:left;border-color:#000000;min-width:120px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Distribution</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 38.8</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 42.1</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 33.9</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 29.6</font></td></tr><tr style="height: 10px"><td colspan="2" style="width: 120px; text-align:left;border-color:#000000;min-width:120px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Transmission</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 41.2</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 40.6</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 41.9</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 47.0</font></td></tr><tr style="height: 10px"><td colspan="2" style="width: 120px; text-align:left;border-color:#000000;min-width:120px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Generation</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 29.6</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 29.6</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 25.0</font></td></tr><tr style="height: 10px"><td colspan="2" style="width: 120px; text-align:left;border-color:#000000;min-width:120px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Other</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 17.7</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td></tr></table></div>
CY2011	us-gaap	Property Plant And Equipment Depreciation Methods PropertyPlantAndEquipmentDepreciationMethods	The provision for depreciation on utility assets is calculated using the straight-line method based on the estimated remaining useful lives of depreciable plant in-service, adjusted for salvage value and removal costs, as approved by the appropriate regulatory agency (the PURA, NHPUC and the DPU for CL&P, PSNH and WMECO, respectively). Depreciation rates are applied to plant-in-service from the time it is placed in service. When a plant is retired from service, the original cost of the plant is charged to the accumulated provision for depreciation, which includes cost of removal less salvage. Cost of removal is classified as a Regulatory Liability on the accompanying consolidated balance sheets.
CY2011	nu	Schedule Of Plant Depreciation Rates ScheduleOfPlantDepreciationRates	<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 10px"><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;"><font style="FONT-STYLE: italic;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: left;">(Percent)</font></td><td colspan="2" style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">2011</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">2010</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">2009</font></td></tr><tr style="height: 10px"><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">NU</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.6</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.7</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.9</font></td></tr><tr style="height: 10px"><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">CL&P</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.4</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.7</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 3.0</font></td></tr><tr style="height: 10px"><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">PSNH</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.9</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.8</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.7</font></td></tr><tr style="height: 10px"><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">WMECO</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.9</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.8</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.9</font></td></tr></table></div>
CY2011	nu	Public Utilities Property Plant And Equipment Depreciation Rates PublicUtilitiesPropertyPlantAndEquipmentDepreciationRates	0.026	pure
CY2010	nu	Public Utilities Property Plant And Equipment Depreciation Rates PublicUtilitiesPropertyPlantAndEquipmentDepreciationRates	0.027	pure
CY2009	nu	Public Utilities Property Plant And Equipment Depreciation Rates PublicUtilitiesPropertyPlantAndEquipmentDepreciationRates	0.029	pure
CY2011Q4	nu	Current Derivative Assets Consolidated CurrentDerivativeAssetsConsolidated	13300000	USD
CY2010Q4	nu	Current Derivative Assets Consolidated CurrentDerivativeAssetsConsolidated	17300000	USD
CY2011	us-gaap	Description Of Derivative Activity Volume DescriptionOfDerivativeActivityVolume	As of December 31, 2011 and 2010, NU had approximately 0.1 million and 0.3 million MWh, respectively, of supply volumes remaining in its unregulated wholesale portfolio when expected sales are compared with contracted supply, both of which extend through 2013.
CY2011Q4	nu	Derivative Assets Subject To Credit Risk With Investment Grade Counterparty DerivativeAssetsSubjectToCreditRiskWithInvestmentGradeCounterparty	102000000	USD
CY2011Q4	us-gaap	Notional Amount Of Fair Value Hedge Instruments NotionalAmountOfFairValueHedgeInstruments	263000000	USD
CY2010	nu	Interest Realized In Earnings On Fair Value Hedge InterestRealizedInEarningsOnFairValueHedge	10900000	USD
CY2011	nu	Interest Realized In Earnings On Fair Value Hedge InterestRealizedInEarningsOnFairValueHedge	10500000	USD
CY2011	us-gaap	Increase Decrease In Fair Value Of Interest Rate Fair Value Hedging Instruments IncreaseDecreaseInFairValueOfInterestRateFairValueHedgingInstruments	1000000	USD
CY2011	us-gaap	Increase Decrease In Fair Value Of Hedged Item In Interest Rate Fair Value Hedge IncreaseDecreaseInFairValueOfHedgedItemInInterestRateFairValueHedge	-1000000	USD
CY2010	us-gaap	Increase Decrease In Fair Value Of Hedged Item In Interest Rate Fair Value Hedge IncreaseDecreaseInFairValueOfHedgedItemInInterestRateFairValueHedge	-9500000	USD
CY2010	us-gaap	Increase Decrease In Fair Value Of Interest Rate Fair Value Hedging Instruments IncreaseDecreaseInFairValueOfInterestRateFairValueHedgingInstruments	9500000	USD
CY2009	us-gaap	Increase Decrease In Fair Value Of Hedged Item In Interest Rate Fair Value Hedge IncreaseDecreaseInFairValueOfHedgedItemInInterestRateFairValueHedge	-1600000	USD
CY2009	nu	Interest Realized In Earnings On Fair Value Hedge InterestRealizedInEarningsOnFairValueHedge	9100000	USD
CY2009	us-gaap	Increase Decrease In Fair Value Of Interest Rate Fair Value Hedging Instruments IncreaseDecreaseInFairValueOfInterestRateFairValueHedgingInstruments	1600000	USD
CY2011	us-gaap	Cash Flow Hedge Gain Loss Reclassified To Interest Expense Net CashFlowHedgeGainLossReclassifiedToInterestExpenseNet	-1300000	USD
CY2010	us-gaap	Cash Flow Hedge Gain Loss Reclassified To Interest Expense Net CashFlowHedgeGainLossReclassifiedToInterestExpenseNet	-400000	USD
CY2011	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Before Tax Period Increase Decrease OtherComprehensiveIncomeDerivativesQualifyingAsHedgesBeforeTaxPeriodIncreaseDecrease	-25100000	USD
CY2009	us-gaap	Cash Flow Hedge Gain Loss Reclassified To Interest Expense Net CashFlowHedgeGainLossReclassifiedToInterestExpenseNet	-400000	USD
CY2011Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	4100000	USD
CY2011Q4	us-gaap	Additional Collateral Aggregate Fair Value AdditionalCollateralAggregateFairValue	19900000	USD
CY2011Q4	nu	Standby Letters Of Credit Posted StandbyLettersOfCreditPosted	0	USD
CY2011Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	23500000	USD
CY2010Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	30900000	USD
CY2010Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	500000	USD
CY2010Q4	us-gaap	Additional Collateral Aggregate Fair Value AdditionalCollateralAggregateFairValue	18500000	USD
CY2010Q4	nu	Standby Letters Of Credit Posted StandbyLettersOfCreditPosted	24000000	USD
CY2009Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	761200000	USD
CY2010Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	840200000	USD
CY2011	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	500000	USD
CY2011	nu	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Gain Loss Included In Reg Asset Liability FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityGainLossIncludedInRegAssetLiability	-161000000	USD
CY2011	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	38500000	USD
CY2010	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	2700000	USD
CY2010	nu	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Gain Loss Included In Reg Asset Liability FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityGainLossIncludedInRegAssetLiability	-81200000	USD
CY2010	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	-500000	USD
CY2011	us-gaap	Fair Value Assets And Liabilities Measured On Recurring Basis Gain Loss Included In Earnings FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings	700000	USD
CY2010	us-gaap	Fair Value Assets And Liabilities Measured On Recurring Basis Gain Loss Included In Earnings FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings	1200000	USD
CY2011	nu	Rollforward Of Net Derivative Asset Liabilities Valued Using Unobservable Inputs RollforwardOfNetDerivativeAssetLiabilitiesValuedUsingUnobservableInputs	<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> <sup></sup></td><td colspan="8" style="width: 320px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:320px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">NU</font></td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> <sup></sup></td><td colspan="2" style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Commodity</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> <sup></sup></td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">and Capacity</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Commodity</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> <sup></sup></td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Contracts</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Supply and</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> <sup></sup></td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Required By</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;"> Price Risk</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> <sup></sup></td><td colspan="2" style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Regulation</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Management</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Total Level 3</font></td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="FONT-STYLE: italic;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: left;">(Millions of Dollars)</font><sup></sup></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="TEXT-DECORATION: underline;FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Derivatives, Net: </font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 12px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Fair Value as of January 1, 2010</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">$</font></td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (720.3)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">$</font></td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (40.9)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">$</font></td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (761.2)</font></td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Net Realized/Unrealized Gains/(Losses) Included in: </font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">Net Income</font><sup>(1)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.7</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.7</font></td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">Regulatory Assets/Liabilities</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (74.0)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (7.2)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (81.2)</font></td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Settlements</font><sup></sup></td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (13.7)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 13.2</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (0.5)</font></td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Fair Value as of December 31, 2010</font><sup></sup></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">$</font></td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (808.0)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">$</font></td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (32.2)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">$</font></td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (840.2)</font></td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Net Realized/Unrealized Gains/(Losses) Included in: </font><sup></sup></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">Net Income</font><sup>(1)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 0.5</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 0.5</font></td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">Regulatory Assets/Liabilities</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (158.1)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (2.9)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (161.0)</font></td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Settlements</font><sup></sup></td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 26.8</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 11.7</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 38.5</font></td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Fair Value as of December 31, 2011</font><sup></sup></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">$</font></td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (939.3)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">$</font></td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (22.9)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">$</font></td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (962.2)</font></td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> <sup></sup></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 11px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Gains Included in Net Income Relating to</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 11px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Items Held as of End of Year:</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">2011</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 0.7</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 0.7</font></td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">2010</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 1.2</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 1.2</font></td></tr></table></div><p style='margin-top: 0pt; margin-bottom: 0pt;'></p><div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"> </td><td colspan="8" style="width: 260px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:260px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">CL&P</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">WMECO</font></td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"> </td><td colspan="2" style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Commodity</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Commodity</font></td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">and Capacity</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Commodity</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">and Capacity</font></td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Contracts</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Supply and</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Contracts</font></td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Required By</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;"> Price Risk</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Required By</font></td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;"><font style="FONT-STYLE: italic;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: left;">(Millions of Dollars)</font></td><td colspan="2" style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Regulation</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Management</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Total Level 3</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">Regulation</font></td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;"><font style="TEXT-DECORATION: underline;FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Derivatives, Net: </font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Fair Value as of January 1, 2010</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (720.3)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 4.5</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (715.8)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Net Realized/Unrealized Losses Included in:</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">Regulatory Assets/Liabilities</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (74.0)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (6.2)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (80.2)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Settlements</font></td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (13.7)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 3.6</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (10.1)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Fair Value as of December 31, 2010</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (808.0)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 1.9</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (806.1)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Net Realized/Unrealized Losses Included in:</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">Regulatory Assets/Liabilities</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (150.8)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (2.8)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (153.6)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (7.3)</font></td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Settlements</font></td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 26.8</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 1.3</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 28.1</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">Fair Value as of December 31, 2011</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (932.0)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 0.4</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (931.6)</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> (7.3)</font></td></tr></table></div>
CY2011Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	962200000	USD
CY2011Q4	nu	Fair Value Of Securities Under Fair Value Option FairValueOfSecuritiesUnderFairValueOption	41100000	USD
CY2010Q4	nu	Fair Value Of Securities Under Fair Value Option FairValueOfSecuritiesUnderFairValueOption	42200000	USD
CY2011	us-gaap	Fair Value Option Changes In Fair Value Gain Loss FairValueOptionChangesInFairValueGainLoss	-1100000	USD
CY2010	us-gaap	Fair Value Option Changes In Fair Value Gain Loss FairValueOptionChangesInFairValueGainLoss	6900000	USD
CY2010Q4	us-gaap	Availableforsale Securities Gross Unrealized Gain AvailableforsaleSecuritiesGrossUnrealizedGain	1300000	USD
CY2011Q4	us-gaap	Availableforsale Securities Gross Unrealized Gain AvailableforsaleSecuritiesGrossUnrealizedGain	2000000	USD
CY2011Q4	us-gaap	Available For Sale Securities Gross Unrealized Losses1 AvailableForSaleSecuritiesGrossUnrealizedLosses1	-200000	USD
CY2011Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	88400000	USD
CY2011Q4	us-gaap	Available For Sale Securities Fair Value Disclosure AvailableForSaleSecuritiesFairValueDisclosure	90200000	USD
CY2010Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	86300000	USD
CY2010Q4	us-gaap	Available For Sale Securities Fair Value Disclosure AvailableForSaleSecuritiesFairValueDisclosure	87300000	USD
CY2010Q4	us-gaap	Available For Sale Securities Gross Unrealized Losses1 AvailableForSaleSecuritiesGrossUnrealizedLosses1	-300000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	29900000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	25400000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	10900000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	22200000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Maturities Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAmortizedCost	88400000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	29900000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	25600000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	11300000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	23400000	USD
CY2011Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	90200000	USD
CY2011Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	131300000	USD
CY2010Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	129500000	USD
CY2010Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	53300000	USD
CY2011	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	2100000	USD
CY2011	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	-800000	USD
CY2011	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	3500000	USD
CY2011	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	-1900000	USD
CY2011Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	56200000	USD
CY2009Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	50600000	USD
CY2010	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	200000	USD
CY2010	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	3300000	USD
CY2010	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	400000	USD
CY2010	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	-1200000	USD
CY2011	us-gaap	Short Term Debt Terms ShortTermDebtTerms	CL&P, PSNH, WMECO and Yankee Gas Credit Agreement: On September 24, 2010, CL&P, PSNH, WMECO and Yankee Gas jointly entered into a three-year unsecured revolving credit facility in the amount of $400 million, which terminates on September 24, 2013. CL&P and PSNH may borrow up to $300 million each under this facility, with WMECO and Yankee Gas able to borrow up to $200 million each, subject to the $400 million maximum aggregate borrowing limit. This total commitment may be increased to $500 million at the request of the borrowers, subject to lender approval. Under this facility, each company can borrow either on a short-term or a long-term basis subject to regulatory approval. NU Parent Credit Agreement:  On September 24, 2010, NU parent entered into a three-year unsecured revolving credit facility in the amount of $500 million, which terminates on September 24, 2013. Subject to the amount of advances outstanding, LOCs can be issued under this facility for periods up to 364 days on the account of NU parent or any of its subsidiaries up to the total amount of the facility. This total commitment may be increased to $600 million at the request of NU parent, subject to lender approval. Under this facility, NU parent can borrow either on a short-term or a long-term basis.
CY2011	nu	Short Term Debt Regulatory Limits ShortTermDebtRegulatoryLimits	:  The amount of short-term borrowings that may be incurred by CL&P and WMECO is subject to periodic approval by the FERC. As a result of the NHPUC having jurisdiction over PSNH's short-term debt, PSNH is not currently required to obtain FERC approval for its short-term borrowings. On November 30, 2011, the FERC granted authorization to allow CL&P and WMECO to incur total short-term borrowings up to a maximum of $450 million and $300 million, respectively, effective January 1, 2012 through December 31, 2013. PSNH is authorized by regulation of the NHPUC to incur short-term borrowings up to 10 percent of net fixed plant. In an order dated December 17, 2010, the NHPUC increased the amount of short-term borrowings authorized for PSNH to a maximum of 10 percent of net fixed plant plus an additional $60 million until further ordered by the NHPUC. As of December 31, 2011, PSNH's short-term debt authorization under the 10 percent of net fixed plant test plus $60 million totaled approximately $270 million. CL&P's certificate of incorporation contains preferred stock provisions restricting the amount of unsecured debt that CL&P may incur, including limiting unsecured indebtedness with a maturity of less than 10 years to 10 percent of total capitalization. In November 2003, CL&P obtained from its preferred stockholders a waiver of such 10 percent limit for a ten-year period expiring in March 2014, provided that all unsecured indebtedness does not exceed 20 percent of total capitalization. As of December 31, 2011, CL&P had $826.3 million of unsecured debt capacity available under this authorization.
CY2011Q4	nu	Letters Of Credit Outstanding Under Line Of Credit LettersOfCreditOutstandingUnderLineOfCredit	17900000	USD
CY2010Q4	nu	Letters Of Credit Outstanding Under Line Of Credit LettersOfCreditOutstandingUnderLineOfCredit	32100000	USD
CY2009Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	18.96
CY2011	us-gaap	Long Term Debt Description LongTermDebtDescription	(1)        On October 24, 2011, CL&P issued $120.5 million of tax-exempt PCRBs carrying a coupon of 4.375 percent that mature on September 1, 2028 and issued $125 million of tax-exempt PCRBs carrying a coupon of 1.25 percent that mature on September 1, 2028 and are subject to mandatory tender for purchase on September 3, 2013. The $125 million of tax-exempt PCRBs were issued with an initial fixed rate term period ending on September 2, 2013, at which time CL&P expects to remarket the PCRBs. The proceeds from these two CL&P issuances were used to refund $245.5 million of PCRBs that carried a coupon of 5.85 percent and had a maturity date of September 1, 2028. (2)        On April 1, 2011, CL&P remarketed the $62 million of tax-exempt PCRBs for a one-year period. The PCRBs, which mature on May 1, 2031, carry a coupon rate of 1.25 percent during the current one-year fixed-rate period and are subject to mandatory tender for purchase on April 1, 2012, at which time CL&P expects to remarket the bonds. (3)        On May 26, 2011, PSNH issued $122 million of first mortgage bonds with a coupon rate of 4.05 percent and a maturity date of June 1, 2021, and used the proceeds to redeem $119.8 million of its tax-exempt 1992 Series D and 1993 Series E PCRBs, each with a maturity date of May 1, 2021 and a coupon rate of 6 percent. The utility plant of CL&P, PSNH and Yankee Gas is subject to the lien of each company's respective first mortgage bond indenture. The CL&P, PSNH and WMECO tax-exempt bonds contain call provisions providing call prices ranging between 100 percent and 102 percent of par. All other long-term debt securities are subject to make-whole provisions. As of December 31, 2011, CL&P had $423.9 million of tax-exempt PCRBs outstanding, $70 million of which is secured by second mortgage liens on transmission assets, junior to the liens of its first mortgage bond indenture. CL&P has $307.5 million of tax-exempt PCRBs secured by first mortgage bonds. If CL&P failed to meet its obligations under the PCRBs, then these first mortgage bonds would become outstanding. As of December 31, 2011, PSNH had $287.5 million in PCRBs outstanding. PSNH's obligation to repay each series of PCRBs is secured by first mortgage bonds and bond insurance. Each such series of first mortgage bonds contains similar terms and provisions as the applicable series of PCRBs. If PSNH failed to meet its obligations under the PCRBs, then these first mortgage bonds would become outstanding. The 2001 Series A PCRBs, in the aggregate principal amount of $89.3 million, bears interest at a rate that is periodically set pursuant to auctions. The Company is not obligated to purchase these PCRBs, which mature in 2021, from the remarketing agent. The weighted average effective interest rate on PSNH's Series A variable-rate PCRBs was 0.21 percent in 2011 and 0.34 percent in 2010. NU's, including CL&P, PSNH and WMECO, long-term debt agreements provide that NU and certain of its subsidiaries must comply with certain financial and non-financial covenants as are customarily included in such agreements, including a consolidated debt to total capitalization ratio. NU and these subsidiaries were in compliance with these covenants as of December 31, 2011. Yankee Gas has certain long-term debt agreements that contain cross-default provisions applicable to all of Yankee Gas’ outstanding first mortgage bond series. The cross-default provisions on Yankee Gas’ Series B Bonds would be triggered if Yankee Gas were to default on a payment due on indebtedness in excess of $2 million. The cross-default provisions on all other series of Yankee Gas’ first mortgage bonds would be triggered if Yankee Gas were to default in a payment due on indebtedness in excess of $10 million. No debt issuances of CL&P, PSNH, WMECO or NU parent contain cross-default provisions as of December 31, 2011. The fair value adjustment relates to the NU parent 7.25 percent note, due 2012 in the amount of $263 million, that is hedged with a fixed to floating interest rate swap. The change in fair value of the interest component of the debt was recorded as an adjustment to Long-Term Debt (Long-Term Debt - Current Portion as of December 31, 2011 since the note was due within one year) with an equal and offsetting adjustment to Derivative Assets for the change in fair value of the fixed to floating interest rate swap. Spent Nuclear Fuel Obligation: Under the Nuclear Waste Policy Act of 1982, CL&P and WMECO must pay the DOE for the costs of disposal of spent nuclear fuel and high-level radioactive waste for the period prior to the sale of their ownership shares in the Millstone nuclear power stations. The DOE is responsible for the selection and development of repositories for, and the disposal of, spent nuclear fuel and high-level radioactive waste. For nuclear fuel used to generate electricity prior to April 7, 1983 (Prior Period Spent Nuclear Fuel) for CL&P and WMECO, an accrual has been recorded for the full liability, and payment must be made by CL&P and WMECO to the DOE prior to the first delivery of spent fuel to the DOE. After the sale of Millstone, CL&P and WMECO remained responsible for their share of the disposal costs associated with the Prior Period Spent Nuclear Fuel. Until such payment to the DOE is made, the outstanding liability will continue to accrue interest at the 3-month Treasury bill yield rate. Fees due to the DOE for the disposal of Prior Period Spent Nuclear Fuel as of December 31, 2011 and 2010 are included in Long-Term Debt, including accumulated interest costs of $219.3 million and $218.9 million ($177.6 million and $177.3 million for CL&P and $41.7 million and $41.6 million for WMECO), respectively. WMECO maintains a trust that holds marketable securities to fund amounts due to the DOE for the disposal of WMECO's Prior Period Spent Nuclear Fuel. For further information on this trust, see Note 5, "Marketable Securities," to the consolidated financial statements.
CY2011Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	329300000	USD
CY2011Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	430000000	USD
CY2011Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	275000000	USD
CY2011Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	150000000	USD
CY2011Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	15400000	USD
CY2011Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	3449600000	USD
CY2011Q4	nu	Longtermdebtmaturitiesrepaymentsofprincipaltotal Longtermdebtmaturitiesrepaymentsofprincipaltotal	4649300000	USD
CY2011Q4	nu	Defined Benefit Plan Benefits Paid Lump Sum DefinedBenefitPlanBenefitsPaidLumpSum	0	USD
CY2011	us-gaap	Defined Benefit Plan Estimated Future Employer Contributions In Next Fiscal Year Description DefinedBenefitPlanEstimatedFutureEmployerContributionsInNextFiscalYearDescription	A contribution of $143.6 million ($112.6 million of which was contributed by PSNH) was made in 2011. Based on the current status of the Pension Plan, NU is required to make a contribution to the Pension Plan of approximately $197.3 million in 2012, which will be made in quarterly installments, to meet minimum current funding requirements under the PPA.
CY2011	nu	Schedule Of Defined Contribution Plans401k ScheduleOfDefinedContributionPlans401k	<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;"><font style="FONT-STYLE: italic;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: left;">(Millions of Dollars)</font></td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">NU</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">CL&P</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">PSNH</font></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">WMECO</font></td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">2011</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">13.2</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">4.0</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">2.5</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.8</font></td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">2010</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 12.7</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">4.0</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">2.4</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.8</font></td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">2009</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 12.2</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">3.9</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">2.3</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.7</font></td></tr></table></div>
CY2011	nu	Schedule Of Defined Contribution Plans K Vantage ScheduleOfDefinedContributionPlansKVantage	<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;"><font style="FONT-STYLE: italic;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: left;">(Millions of Dollars)</font></td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">NU</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">CL&P</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">PSNH</font></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;"><font style="FONT-WEIGHT: bold;FONT-FAMILY: Arial;FONT-SIZE: 7pt;COLOR: #000000;TEXT-ALIGN: center;">WMECO</font></td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">2011</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">4.2</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.5</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.6</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">$</font></td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.1</font></td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">2010</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 3.4</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.4</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.4</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.1</font></td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: left;">2009</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> 2.6</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.2</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;">0.3</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"><font style="FONT-FAMILY: Arial;FONT-SIZE: 8pt;COLOR: #000000;"> -</font></td></tr></table></div>
CY2011	us-gaap	Employee Stock Ownership Plan Esop Debt Structure Employer Loan Description EmployeeStockOwnershipPlanESOPDebtStructureEmployerLoanDescription	NU issued unsecured notes during 1991 and 1992 totaling $250 million, the proceeds of which were loaned to the ESOP trust (ESOP Notes) for the purchase of 10.8 million newly issued NU common shares (ESOP shares). During 2010, the ESOP Notes were fully repaid and all ESOP shares purchased with the proceeds of the ESOP Notes were fully allocated. As of December 31, 2011 and 2010, total allocated ESOP shares were 10,800,185. Following complete allocation of the ESOP shares, continuing allocations of NU common shares were made from NU treasury shares to satisfy the 401(k) Savings Plan obligation to provide a portion of the matching contribution in NU common shares.
CY2010	us-gaap	Employee Stock Ownership Plan Esop Cash Contributions To Esop EmployeeStockOwnershipPlanESOPCashContributionsToESOP	1100000	USD
CY2009	us-gaap	Employee Stock Ownership Plan Esop Cash Contributions To Esop EmployeeStockOwnershipPlanESOPCashContributionsToESOP	6100000	USD
CY2011	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	8800000	USD
CY2010	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	8500000	USD
CY2009	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	8200000	USD
CY2010Q4	us-gaap	Employee Stock Ownership Plan Esop Number Of Allocated Shares EmployeeStockOwnershipPlanESOPNumberOfAllocatedShares	127054	shares
CY2010Q4	nu	Employee Stock Ownership Plan Esop Numberof Allocated Shares In Total EmployeeStockOwnershipPlanESOPNumberofAllocatedSharesInTotal	10800185	shares
CY2011Q4	nu	Employee Stock Ownership Plan Esop Numberof Allocated Shares In Total EmployeeStockOwnershipPlanESOPNumberofAllocatedSharesInTotal	10800185	shares
CY2011	us-gaap	Employee Stock Ownership Plan Esop Dividends Paid To Esop EmployeeStockOwnershipPlanESOPDividendsPaidToESOP	0.275	USD
CY2010	us-gaap	Employee Stock Ownership Plan Esop Dividends Paid To Esop EmployeeStockOwnershipPlanESOPDividendsPaidToESOP	0.25625	USD
CY2009	us-gaap	Employee Stock Ownership Plan Esop Dividends Paid To Esop EmployeeStockOwnershipPlanESOPDividendsPaidToESOP	0.2375	USD
CY2011	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	1300000	USD
CY2010	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	900000	USD
CY2009	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	900000	USD
CY2011Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	4500000	shares
CY2011Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	2685615	shares
CY2010Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	3068850	shares
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Compensation Cost ShareBasedCompensationArrangementByShareBasedPaymentAwardCompensationCost	12300000	USD
CY2010	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Compensation Cost ShareBasedCompensationArrangementByShareBasedPaymentAwardCompensationCost	10500000	USD
CY2009	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Compensation Cost ShareBasedCompensationArrangementByShareBasedPaymentAwardCompensationCost	8800000	USD
CY2011	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4900000	USD
CY2010	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4200000	USD
CY2009	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	3500000	USD
CY2011Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	8900000	USD
CY2011	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition	1.77	pure
CY2011Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm1	0.3	pure
CY2008Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	320920	shares
CY2009	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	-95704	shares
CY2009	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	0	shares
CY2009Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	225216	shares
CY2010	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	-112617	shares
CY2010	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	0	shares
CY2010Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	112599	shares
CY2011	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	-65225	shares
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	0	shares
CY2011Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	47374	shares
CY2008	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Lower Range Limit ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit	14.94
CY2009	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Lower Range Limit ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit	17.40
CY2010	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Lower Range Limit ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit	17.40
CY2011	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Lower Range Limit ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit	18.58
CY2008	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Upper Range Limit ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit	21.03
CY2009	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Upper Range Limit ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit	21.03
CY2010	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Upper Range Limit ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit	21.03
CY2011	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Upper Range Limit ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit	18.90
CY2008Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	18.83
CY2011Q4	nu	Employee Stock Purchase Plan Shares Remaining For Future Issuance EmployeeStockPurchasePlanSharesRemainingForFutureIssuance	896702	shares
CY2010Q4	nu	Employee Stock Purchase Plan Shares Remaining For Future Issuance EmployeeStockPurchasePlanSharesRemainingForFutureIssuance	932178	shares
CY2011	nu	Espp Discounted Purchase Price First Six Months ESPPDiscountedPurchasePriceFirstSixMonths	31.27	USD
CY2011	nu	Espp Discounted Purchase Price Second Six Months ESPPDiscountedPurchasePriceSecondSixMonths	32.30	USD
CY2010	nu	Espp Discounted Purchase Price First Six Months ESPPDiscountedPurchasePriceFirstSixMonths	26.45	USD
CY2010Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	18.80
CY2011Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	18.78
CY2009Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	18.54
CY2010Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	19.12
CY2011Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	18.81
CY2009	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	0

CY2011Q4

us-gaap

Capital Leases Future Minimum Payments Due Current

CapitalLeasesFutureMinimumPaymentsDueCurrent

3000000

USD

CY2011Q4

us-gaap

Cash

6559000

USD

CY2011Q4

us-gaap

Accounts Receivable Net Current

AccountsReceivableNetCurrent

488002000

USD

CY2011Q4

us-gaap

Costs In Excess Of Billings On Uncompleted Contracts Or Programs Expected To Be Collected Within One Year

CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear

175207000

USD

CY2011Q4

us-gaap

Income Taxes Receivable

IncomeTaxesReceivable

4931000

USD

CY2011Q4

us-gaap

Energy Related Inventory

EnergyRelatedInventory

248958000

USD

CY2011Q4

us-gaap

Marketable Securities Current

MarketableSecuritiesCurrent

70970000

USD

CY2011Q4

us-gaap

Other Assets Current

OtherAssetsCurrent

107701000

USD

CY2011Q4

us-gaap

Assets Current

AssetsCurrent

1357472000

USD

CY2010Q4

us-gaap

Cash

23395000

USD

CY2010Q4

us-gaap

Accounts Receivable Net Current

AccountsReceivableNetCurrent

523644000

USD

CY2010Q4

us-gaap

Costs In Excess Of Billings On Uncompleted Contracts Or Programs Expected To Be Collected Within One Year

CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear

208834000

USD

CY2010Q4

us-gaap

Income Taxes Receivable

IncomeTaxesReceivable

89638000

USD

CY2010Q4

us-gaap

Energy Related Inventory

EnergyRelatedInventory

244043000

USD

CY2010Q4

us-gaap

Marketable Securities Current

MarketableSecuritiesCurrent

78306000

USD

CY2010Q4

us-gaap

Other Assets Current

OtherAssetsCurrent

100441000

USD

CY2010Q4

us-gaap

Assets Current

AssetsCurrent

1507000000

USD

CY2011Q4

us-gaap

Regulatory Assets Noncurrent

RegulatoryAssetsNoncurrent

3267710000

USD

CY2010Q4

us-gaap

Regulatory Assets Noncurrent

RegulatoryAssetsNoncurrent

2756580000

USD

CY2011Q4

us-gaap

Goodwill

287591000

USD

CY2010Q4

us-gaap

Goodwill

287591000

USD

CY2011Q4

us-gaap

Marketable Securities Noncurrent

MarketableSecuritiesNoncurrent

60311000

USD

CY2010Q4

us-gaap

Marketable Securities Noncurrent

MarketableSecuritiesNoncurrent

51201000

USD

CY2011Q4

us-gaap

Derivative Assets Noncurrent

DerivativeAssetsNoncurrent

98357000

USD

CY2010Q4

us-gaap

Derivative Assets Noncurrent

DerivativeAssetsNoncurrent

123242000

USD

CY2011Q4

us-gaap

Other Assets Noncurrent

OtherAssetsNoncurrent

172560000

USD

CY2010Q4

us-gaap

Other Assets Noncurrent

OtherAssetsNoncurrent

179261000

USD

CY2011Q4

us-gaap

Assets Noncurrent

AssetsNoncurrent

3886529000

USD

CY2010Q4

us-gaap

Assets Noncurrent

AssetsNoncurrent

3397875000

USD

CY2011Q4

us-gaap

Assets

15647066000

USD

CY2010Q4

us-gaap

Assets

14472601000

USD

CY2011Q4

us-gaap

Regulatory Assets Current

RegulatoryAssetsCurrent

255144000

USD

CY2010Q4

us-gaap

Regulatory Assets Current

RegulatoryAssetsCurrent

238699000

USD

CY2011Q4

us-gaap

Public Utilities Property Plant And Equipment Net

PublicUtilitiesPropertyPlantAndEquipmentNet

10403065000

USD

CY2010Q4

us-gaap

Public Utilities Property Plant And Equipment Net

PublicUtilitiesPropertyPlantAndEquipmentNet

9567726000

USD

CY2011Q4

us-gaap

Notes Payable To Bank Current

NotesPayableToBankCurrent

317000000

USD

CY2010Q4

us-gaap

Notes Payable To Bank Current

NotesPayableToBankCurrent

267000000

USD

CY2011Q4

us-gaap

Long Term Debt Current

LongTermDebtCurrent

331582000

USD

CY2010Q4

us-gaap

Long Term Debt Current

LongTermDebtCurrent

66286000

USD

CY2011Q4

us-gaap

Accounts Payable Current

AccountsPayableCurrent

633282000

USD

CY2010Q4

us-gaap

Accounts Payable Current

AccountsPayableCurrent

417285000

USD

CY2011Q4

us-gaap

Accounts Payable Other Current

AccountsPayableOtherCurrent

75068000

USD

CY2010Q4

us-gaap

Accounts Payable Other Current

AccountsPayableOtherCurrent

74659000

USD

CY2011Q4

us-gaap

Accrued Income Taxes Current

AccruedIncomeTaxesCurrent

69592000

USD

CY2010Q4

us-gaap

Accrued Income Taxes Current

AccruedIncomeTaxesCurrent

107067000

USD

CY2011Q4

us-gaap

Interest Payable Current

InterestPayableCurrent

69198000

USD

CY2010Q4

us-gaap

Interest Payable Current

InterestPayableCurrent

74740000

USD

CY2010

us-gaap

Revenues

4898167000

USD

CY2011Q4

us-gaap

Derivative Liabilities Current

DerivativeLiabilitiesCurrent

107558000

USD

CY2010Q4

us-gaap

Derivative Liabilities Current

DerivativeLiabilitiesCurrent

71501000

USD

CY2011Q4

us-gaap

Other Liabilities Current

OtherLiabilitiesCurrent

176558000

USD

CY2010Q4

us-gaap

Other Liabilities Current

OtherLiabilitiesCurrent

167206000

USD

CY2011Q4

us-gaap

Liabilities Current

LiabilitiesCurrent

1947682000

USD

CY2010Q4

us-gaap

Liabilities Current

LiabilitiesCurrent

1345147000

USD

CY2011Q4

us-gaap

Secured Long Term Debt

SecuredLongTermDebt

112260000

USD

CY2010Q4

us-gaap

Secured Long Term Debt

SecuredLongTermDebt

181572000

USD

CY2011Q4

us-gaap

Deferred Tax Liabilities Noncurrent

DeferredTaxLiabilitiesNoncurrent

1868316000

USD

CY2010Q4

us-gaap

Deferred Tax Liabilities Noncurrent

DeferredTaxLiabilitiesNoncurrent

1636750000

USD

CY2011Q4

us-gaap

Regulatory Liability Noncurrent

RegulatoryLiabilityNoncurrent

266145000

USD

CY2010Q4

us-gaap

Regulatory Liability Noncurrent

RegulatoryLiabilityNoncurrent

339655000

USD

CY2011Q4

us-gaap

Derivative Liabilities Noncurrent

DerivativeLiabilitiesNoncurrent

959876000

USD

CY2010Q4

us-gaap

Derivative Liabilities Noncurrent

DerivativeLiabilitiesNoncurrent

909668000

USD

CY2011Q4

us-gaap

Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent

PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

1326037000

USD

CY2010Q4

us-gaap

Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent

PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

1050614000

USD

CY2011Q4

us-gaap

Other Liabilities Noncurrent

OtherLiabilitiesNoncurrent

420011000

USD

CY2010Q4

us-gaap

Other Liabilities Noncurrent

OtherLiabilitiesNoncurrent

447496000

USD

CY2011Q4

us-gaap

Liabilities Noncurrent

LiabilitiesNoncurrent

4840385000

USD

CY2010Q4

us-gaap

Liabilities Noncurrent

LiabilitiesNoncurrent

4384183000

USD

CY2011Q4

us-gaap

Long Term Debt Noncurrent

LongTermDebtNoncurrent

4614913000

USD

CY2010Q4

us-gaap

Long Term Debt Noncurrent

LongTermDebtNoncurrent

4632866000

USD

CY2011Q4

us-gaap

Temporary Equity Carrying Amount

TemporaryEquityCarryingAmount

116200000

USD

CY2010Q4

us-gaap

Temporary Equity Carrying Amount

TemporaryEquityCarryingAmount

116200000

USD

CY2011Q4

us-gaap

Common Stock Value

CommonStockValue

980264000

USD

CY2010Q4

us-gaap

Common Stock Value

CommonStockValue

978909000

USD

CY2011Q4

us-gaap

Additional Paid In Capital

AdditionalPaidInCapital

1797884000

USD

CY2010Q4

us-gaap

Additional Paid In Capital

AdditionalPaidInCapital

1777592000

USD

CY2011Q4

us-gaap

Retained Earnings Accumulated Deficit

RetainedEarningsAccumulatedDeficit

1651875000

USD

CY2010Q4

us-gaap

Retained Earnings Accumulated Deficit

RetainedEarningsAccumulatedDeficit

1452777000

USD

CY2011Q4

us-gaap

Accumulated Other Comprehensive Income Loss Net Of Tax

AccumulatedOtherComprehensiveIncomeLossNetOfTax

70686000

USD

CY2010Q4

us-gaap

Accumulated Other Comprehensive Income Loss Net Of Tax

AccumulatedOtherComprehensiveIncomeLossNetOfTax

43370000

USD

CY2011Q4

us-gaap

Treasury Stock Value

TreasuryStockValue

-346667000

USD

CY2010Q4

us-gaap

Treasury Stock Value

TreasuryStockValue

-354732000

USD

CY2011Q4

us-gaap

Stockholders Equity

StockholdersEquity

4012670000

USD

CY2010Q4

us-gaap

Stockholders Equity

StockholdersEquity

3811176000

USD

CY2011Q4

us-gaap

Minority Interest

MinorityInterest

2956000

USD

CY2010Q4

us-gaap

Minority Interest

MinorityInterest

1457000

USD

CY2011Q4

us-gaap

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

4015626000

USD

CY2010Q4

us-gaap

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

3812633000

USD

CY2011Q4

us-gaap

Capitalization Longterm Debt And Equity

CapitalizationLongtermDebtAndEquity

8746739000

USD

CY2010Q4

us-gaap

Capitalization Longterm Debt And Equity

CapitalizationLongtermDebtAndEquity

8561699000

USD

CY2011Q4

us-gaap

Liabilities And Stockholders Equity

LiabilitiesAndStockholdersEquity

15647066000

USD

CY2010Q4

us-gaap

Liabilities And Stockholders Equity

LiabilitiesAndStockholdersEquity

14472601000

USD

CY2011Q4

us-gaap

Regulatory Liability Current

RegulatoryLiabilityCurrent

167844000

USD

CY2010Q4

us-gaap

Regulatory Liability Current

RegulatoryLiabilityCurrent

99403000

USD

CY2011

us-gaap

Revenues

4465657000

USD

CY2009

us-gaap

Revenues

5439430000

USD

CY2011

us-gaap

Cost Of Purchased Power

CostOfPurchasedPower

1580683000

USD

CY2010

us-gaap

Cost Of Purchased Power

CostOfPurchasedPower

1985634000

USD

CY2009

us-gaap

Cost Of Purchased Power

CostOfPurchasedPower

2629619000

USD

CY2011

us-gaap

Other Cost And Expense Operating

OtherCostAndExpenseOperating

1026192000

USD

CY2010

us-gaap

Other Cost And Expense Operating

OtherCostAndExpenseOperating

958417000

USD

CY2009

us-gaap

Other Cost And Expense Operating

OtherCostAndExpenseOperating

1001190000

USD

CY2011

us-gaap

Maintenance Costs

MaintenanceCosts

271779000

USD

CY2010

us-gaap

Maintenance Costs

MaintenanceCosts

210283000

USD

CY2009

us-gaap

Maintenance Costs

MaintenanceCosts

234173000

USD

CY2011

us-gaap

Depreciation

302192000

USD

CY2010

us-gaap

Depreciation

300737000

USD

CY2009

us-gaap

Depreciation

309618000

USD

CY2011

us-gaap

Amortization Of Regulatory Asset

AmortizationOfRegulatoryAsset

97113000

USD

CY2010

us-gaap

Amortization Of Regulatory Asset

AmortizationOfRegulatoryAsset

95593000

USD

CY2009

us-gaap

Amortization Of Regulatory Asset

AmortizationOfRegulatoryAsset

13315000

USD

CY2011

us-gaap

Other Depreciation And Amortization

OtherDepreciationAndAmortization

69912000

USD

CY2010

us-gaap

Other Depreciation And Amortization

OtherDepreciationAndAmortization

232871000

USD

CY2009

us-gaap

Other Depreciation And Amortization

OtherDepreciationAndAmortization

217941000

USD

CY2011

us-gaap

Taxes Excluding Income And Excise Taxes

TaxesExcludingIncomeAndExciseTaxes

323610000

USD

CY2010

us-gaap

Taxes Excluding Income And Excise Taxes

TaxesExcludingIncomeAndExciseTaxes

314741000

USD

CY2009

us-gaap

Taxes Excluding Income And Excise Taxes

TaxesExcludingIncomeAndExciseTaxes

282199000

USD

CY2011

us-gaap

Operating Expenses

OperatingExpenses

3671481000

USD

CY2010

us-gaap

Operating Expenses

OperatingExpenses

4098276000

USD

CY2009

us-gaap

Operating Expenses

OperatingExpenses

4688055000

USD

CY2011

us-gaap

Operating Income Loss

OperatingIncomeLoss

794176000

USD

CY2010

us-gaap

Operating Income Loss

OperatingIncomeLoss

799891000

USD

CY2009

us-gaap

Operating Income Loss

OperatingIncomeLoss

751375000

USD

CY2011

us-gaap

Interest Expense Long Term Debt

InterestExpenseLongTermDebt

231630000

USD

CY2010

us-gaap

Interest Expense Long Term Debt

InterestExpenseLongTermDebt

231089000

USD

CY2009

us-gaap

Interest Expense Long Term Debt

InterestExpenseLongTermDebt

224712000

USD

CY2011

us-gaap

Interest Expense Other Long Term Debt

InterestExpenseOtherLongTermDebt

8611000

USD

CY2010

us-gaap

Interest Expense Other Long Term Debt

InterestExpenseOtherLongTermDebt

20573000

USD

CY2009

us-gaap

Interest Expense Other Long Term Debt

InterestExpenseOtherLongTermDebt

36524000

USD

CY2011

us-gaap

Interest Expense Other

InterestExpenseOther

10184000

USD

CY2010

us-gaap

Interest Expense Other

InterestExpenseOther

-14371000

USD

CY2009

us-gaap

Interest Expense Other

InterestExpenseOther

12401000

USD

CY2011

us-gaap

Interest Expense

InterestExpense

250425000

USD

CY2010

us-gaap

Interest Expense

InterestExpense

237291000

USD

CY2009

us-gaap

Interest Expense

InterestExpense

273637000

USD

CY2011

us-gaap

Other Nonoperating Income Expense

OtherNonoperatingIncomeExpense

27715000

USD

CY2010

us-gaap

Other Nonoperating Income Expense

OtherNonoperatingIncomeExpense

41916000

USD

CY2009

us-gaap

Other Nonoperating Income Expense

OtherNonoperatingIncomeExpense

37801000

USD

CY2011

us-gaap

Income Loss From Continuing Operations Before Income Taxes Domestic

IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic

571466000

USD

CY2010

us-gaap

Income Loss From Continuing Operations Before Income Taxes Domestic

IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic

604516000

USD

CY2009

us-gaap

Income Loss From Continuing Operations Before Income Taxes Domestic

IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic

515539000

USD

CY2011

us-gaap

Income Tax Expense Benefit

IncomeTaxExpenseBenefit

170953000

USD

CY2010

us-gaap

Income Tax Expense Benefit

IncomeTaxExpenseBenefit

210409000

USD

CY2009

us-gaap

Income Tax Expense Benefit

IncomeTaxExpenseBenefit

179947000

USD

CY2011

us-gaap

Net Income Loss

NetIncomeLoss

400513000

USD

CY2010

us-gaap

Net Income Loss

NetIncomeLoss

394107000

USD

CY2009

us-gaap

Net Income Loss

NetIncomeLoss

335592000

USD

CY2011

us-gaap

Net Income Loss Attributable To Noncontrolling Interest

NetIncomeLossAttributableToNoncontrollingInterest

5820000

USD

CY2010

us-gaap

Net Income Loss Attributable To Noncontrolling Interest

NetIncomeLossAttributableToNoncontrollingInterest

6158000

USD

CY2009

us-gaap

Net Income Loss Attributable To Noncontrolling Interest

NetIncomeLossAttributableToNoncontrollingInterest

5559000

USD

CY2011

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

394693000

USD

CY2010

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

387949000

USD

CY2009

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

330033000

USD

CY2011

us-gaap

Weighted Average Number Of Diluted Shares Outstanding

WeightedAverageNumberOfDilutedSharesOutstanding

177804568

shares

CY2010

us-gaap

Weighted Average Number Of Diluted Shares Outstanding

WeightedAverageNumberOfDilutedSharesOutstanding

176885387

shares

CY2009

us-gaap

Weighted Average Number Of Diluted Shares Outstanding

WeightedAverageNumberOfDilutedSharesOutstanding

172717246

shares

CY2011

us-gaap

Weighted Average Number Of Shares Outstanding Basic

WeightedAverageNumberOfSharesOutstandingBasic

177410167

shares

CY2010

us-gaap

Weighted Average Number Of Shares Outstanding Basic

WeightedAverageNumberOfSharesOutstandingBasic

176636086

shares

CY2009

us-gaap

Weighted Average Number Of Shares Outstanding Basic

WeightedAverageNumberOfSharesOutstandingBasic

172567928

shares

CY2011

us-gaap

Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPeriodIncreaseDecrease

-14177000

USD

CY2010

us-gaap

Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPeriodIncreaseDecrease

200000

USD

CY2011

us-gaap

Other Comprehensive Income Available For Sale Securities Adjustment Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecrease

506000

USD

CY2010

us-gaap

Other Comprehensive Income Available For Sale Securities Adjustment Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecrease

402000

USD

CY2009

us-gaap

Other Comprehensive Income Available For Sale Securities Adjustment Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecrease

-976000

USD

CY2011

us-gaap

Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecrease

-13645000

USD

CY2010

us-gaap

Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecrease

-505000

USD

CY2009

us-gaap

Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecrease

-5426000

USD

CY2011

us-gaap

Other Comprehensive Income Loss Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease

-27316000

USD

CY2010

us-gaap

Other Comprehensive Income Loss Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease

97000

USD

CY2009

us-gaap

Other Comprehensive Income Loss Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease

-6202000

USD

CY2011

us-gaap

Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest

ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest

5820000

USD

CY2010

us-gaap

Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest

ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest

6158000

USD

CY2009

us-gaap

Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest

ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest

5559000

USD

CY2011

us-gaap

Comprehensive Income Net Of Tax

ComprehensiveIncomeNetOfTax

367377000

USD

CY2010

us-gaap

Comprehensive Income Net Of Tax

ComprehensiveIncomeNetOfTax

388046000

USD

CY2009

us-gaap

Comprehensive Income Net Of Tax

ComprehensiveIncomeNetOfTax

323831000

USD

CY2009

us-gaap

Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Period Increase Decrease

OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPeriodIncreaseDecrease

200000

USD

CY2011

us-gaap

Provision For Doubtful Accounts

ProvisionForDoubtfulAccounts

16420000

USD

CY2009

us-gaap

Provision For Doubtful Accounts

ProvisionForDoubtfulAccounts

53947000

USD

CY2011

us-gaap

Deferred Income Tax Expense Benefit

DeferredIncomeTaxExpenseBenefit

196761000

USD

CY2009

us-gaap

Deferred Income Tax Expense Benefit

DeferredIncomeTaxExpenseBenefit

125890000

USD

CY2011

us-gaap

Pension And Other Postretirement Benefit Expense

PensionAndOtherPostretirementBenefitExpense

133000000

USD

CY2011

us-gaap

Increase Decrease In Regulatory Assets And Liabilities

IncreaseDecreaseInRegulatoryAssetsAndLiabilities

76896000

USD

CY2009

us-gaap

Increase Decrease In Regulatory Assets And Liabilities

IncreaseDecreaseInRegulatoryAssetsAndLiabilities

-37868000

USD

CY2009

us-gaap

Pension And Other Postretirement Benefit Expense

PensionAndOtherPostretirementBenefitExpense

58732000

USD

CY2011

us-gaap

Increase Decrease In Fair Value Of Unhedged Derivative Instruments

IncreaseDecreaseInFairValueOfUnhedgedDerivativeInstruments

35441000

USD

CY2009

us-gaap

Increase Decrease In Fair Value Of Unhedged Derivative Instruments

IncreaseDecreaseInFairValueOfUnhedgedDerivativeInstruments

18798000

USD

CY2011

us-gaap

Other Noncash Income Expense

OtherNoncashIncomeExpense

-29751000

USD

CY2009

us-gaap

Other Noncash Income Expense

OtherNoncashIncomeExpense

-26003000

USD

CY2011

us-gaap

Increase Decrease In Receivables

IncreaseDecreaseInReceivables

-17570000

USD

CY2009

us-gaap

Increase Decrease In Receivables

IncreaseDecreaseInReceivables

-91081000

USD

CY2011

us-gaap

Increase Decrease In Inventories

IncreaseDecreaseInInventories

11033000

USD

CY2009

us-gaap

Increase Decrease In Inventories

IncreaseDecreaseInInventories

-25957000

USD

CY2011

us-gaap

Increase Decrease In Income Taxes Receivable

IncreaseDecreaseInIncomeTaxesReceivable

-49642000

USD

CY2009

us-gaap

Increase Decrease In Income Taxes Receivable

IncreaseDecreaseInIncomeTaxesReceivable

-16194000

USD

CY2011

us-gaap

Increase Decrease In Accounts Payable

IncreaseDecreaseInAccountsPayable

18916000

USD

CY2009

us-gaap

Increase Decrease In Accounts Payable

IncreaseDecreaseInAccountsPayable

-208180000

USD

CY2011

us-gaap

Increase Decrease In Other Operating Capital Net

IncreaseDecreaseInOtherOperatingCapitalNet

-12569000

USD

CY2009

us-gaap

Increase Decrease In Other Operating Capital Net

IncreaseDecreaseInOtherOperatingCapitalNet

6876000

USD

CY2011

us-gaap

Net Cash Provided By Used In Operating Activities

NetCashProvidedByUsedInOperatingActivities

970386000

USD

CY2009

us-gaap

Net Cash Provided By Used In Operating Activities

NetCashProvidedByUsedInOperatingActivities

989118000

USD

CY2011

us-gaap

Payments To Acquire Property Plant And Equipment

PaymentsToAcquirePropertyPlantAndEquipment

1076730000

USD

CY2009

us-gaap

Payments To Acquire Property Plant And Equipment

PaymentsToAcquirePropertyPlantAndEquipment

908146000

USD

CY2011

us-gaap

Proceeds From Sale And Maturity Of Marketable Securities

ProceedsFromSaleAndMaturityOfMarketableSecurities

149441000

USD

CY2009

us-gaap

Proceeds From Sale And Maturity Of Marketable Securities

ProceedsFromSaleAndMaturityOfMarketableSecurities

208947000

USD

CY2011

us-gaap

Payments To Acquire Marketable Securities

PaymentsToAcquireMarketableSecurities

151972000

USD

CY2011

us-gaap

Payments For Proceeds From Other Investing Activities

PaymentsForProceedsFromOtherInvestingActivities

-13833000

USD

CY2011

us-gaap

Net Cash Provided By Used In Investing Activities

NetCashProvidedByUsedInInvestingActivities

-1018587000

USD

CY2009

us-gaap

Payments Of Dividends Common Stock

PaymentsOfDividendsCommonStock

162381000

USD

CY2009

us-gaap

Payments Of Dividends Preferred Stock And Preference Stock

PaymentsOfDividendsPreferredStockAndPreferenceStock

5559000

USD

CY2011

us-gaap

Repayments Of Secured Debt

RepaymentsOfSecuredDebt

69312000

USD

CY2011

us-gaap

Proceeds From Payments For Other Financing Activities

ProceedsFromPaymentsForOtherFinancingActivities

-7123000

USD

CY2011

us-gaap

Net Cash Provided By Used In Financing Activities

NetCashProvidedByUsedInFinancingActivities

31365000

USD

CY2011

us-gaap

Cash And Cash Equivalents Period Increase Decrease

CashAndCashEquivalentsPeriodIncreaseDecrease

-16836000

USD

CY2011

us-gaap

Pension Contributions

PensionContributions

191101000

USD

CY2009

us-gaap

Pension Contributions

PensionContributions

37160000

USD

CY2011

us-gaap

Proceeds From Sale Of Property Plant And Equipment

ProceedsFromSaleOfPropertyPlantAndEquipment

46841000

USD

CY2009

us-gaap

Proceeds From Sale Of Property Plant And Equipment

ProceedsFromSaleOfPropertyPlantAndEquipment

0

USD

CY2011

us-gaap

Repayments Of Long Term Debt

RepaymentsOfLongTermDebt

369586000

USD

CY2010

us-gaap

Provision For Doubtful Accounts

ProvisionForDoubtfulAccounts

31352000

USD

CY2010

us-gaap

Deferred Income Tax Expense Benefit

DeferredIncomeTaxExpenseBenefit

210939000

USD

CY2010

us-gaap

Pension And Other Postretirement Benefit Expense

PensionAndOtherPostretirementBenefitExpense

103861000

USD

CY2010

us-gaap

Pension Contributions

PensionContributions

90633000

USD

CY2010

us-gaap

Increase Decrease In Regulatory Assets And Liabilities

IncreaseDecreaseInRegulatoryAssetsAndLiabilities

-20750000

USD

CY2010

us-gaap

Increase Decrease In Fair Value Of Unhedged Derivative Instruments

IncreaseDecreaseInFairValueOfUnhedgedDerivativeInstruments

11812000

USD

CY2010

us-gaap

Other Noncash Income Expense

OtherNoncashIncomeExpense

-72151000

USD

CY2010

us-gaap

Increase Decrease In Receivables

IncreaseDecreaseInReceivables

51285000

USD

CY2010

us-gaap

Increase Decrease In Inventories

IncreaseDecreaseInInventories

-38126000

USD

CY2010

us-gaap

Increase Decrease In Income Taxes Receivable

IncreaseDecreaseInIncomeTaxesReceivable

82103000

USD

CY2010

us-gaap

Increase Decrease In Accounts Payable

IncreaseDecreaseInAccountsPayable

-44355000

USD

CY2010

us-gaap

Increase Decrease In Other Operating Capital Net

IncreaseDecreaseInOtherOperatingCapitalNet

-17466000

USD

CY2010

us-gaap

Net Cash Provided By Used In Operating Activities

NetCashProvidedByUsedInOperatingActivities

1093463000

USD

CY2010

us-gaap

Payments To Acquire Property Plant And Equipment

PaymentsToAcquirePropertyPlantAndEquipment

954472000

USD

CY2010

us-gaap

Proceeds From Sale And Maturity Of Marketable Securities

ProceedsFromSaleAndMaturityOfMarketableSecurities

174865000

USD

CY2010

us-gaap

Payments To Acquire Marketable Securities

PaymentsToAcquireMarketableSecurities

177204000

USD

CY2010

us-gaap

Proceeds From Sale Of Property Plant And Equipment

ProceedsFromSaleOfPropertyPlantAndEquipment

0

USD

CY2010

us-gaap

Payments For Proceeds From Other Investing Activities

PaymentsForProceedsFromOtherInvestingActivities

1157000

USD

CY2010

us-gaap

Net Cash Provided By Used In Investing Activities

NetCashProvidedByUsedInInvestingActivities

-957968000

USD

CY2009

us-gaap

Proceeds From Repayments Of Short Term Debt

ProceedsFromRepaymentsOfShortTermDebt

-518584000

USD

CY2009

us-gaap

Proceeds From Issuance Of Long Term Debt

ProceedsFromIssuanceOfLongTermDebt

462000000

USD

CY2010

us-gaap

Repayments Of Secured Debt

RepaymentsOfSecuredDebt

260864000

USD

CY2010

us-gaap

Repayments Of Long Term Debt

RepaymentsOfLongTermDebt

4286000

USD

CY2010

us-gaap

Proceeds From Payments For Other Financing Activities

ProceedsFromPaymentsForOtherFinancingActivities

512000

USD

CY2010

us-gaap

Net Cash Provided By Used In Financing Activities

NetCashProvidedByUsedInFinancingActivities

-139052000

USD

CY2010

us-gaap

Cash And Cash Equivalents Period Increase Decrease

CashAndCashEquivalentsPeriodIncreaseDecrease

-3557000

USD

CY2009

us-gaap

Payments To Acquire Marketable Securities

PaymentsToAcquireMarketableSecurities

211243000

USD

CY2009

us-gaap

Payments For Proceeds From Other Investing Activities

PaymentsForProceedsFromOtherInvestingActivities

-7963000

USD

CY2009

us-gaap

Net Cash Provided By Used In Investing Activities

NetCashProvidedByUsedInInvestingActivities

-902479000

USD

CY2008Q4

us-gaap

Cash

89816000

USD

CY2009Q4

us-gaap

Cash

26952000

USD

CY2011

us-gaap

Proceeds From Issuance Or Sale Of Equity

ProceedsFromIssuanceOrSaleOfEquity

0

USD

CY2011

us-gaap

Payments Of Dividends Common Stock

PaymentsOfDividendsCommonStock

194555000

USD

CY2011

us-gaap

Payments Of Dividends Preferred Stock And Preference Stock

PaymentsOfDividendsPreferredStockAndPreferenceStock

5559000

USD

CY2011

us-gaap

Proceeds From Repayments Of Short Term Debt

ProceedsFromRepaymentsOfShortTermDebt

50000000

USD

CY2011

us-gaap

Proceeds From Issuance Of Long Term Debt

ProceedsFromIssuanceOfLongTermDebt

627500000

USD

CY2010

us-gaap

Proceeds From Issuance Or Sale Of Equity

ProceedsFromIssuanceOrSaleOfEquity

0

USD

CY2010

us-gaap

Payments Of Dividends Common Stock

PaymentsOfDividendsCommonStock

180542000

USD

CY2010

us-gaap

Payments Of Dividends Preferred Stock And Preference Stock

PaymentsOfDividendsPreferredStockAndPreferenceStock

5559000

USD

CY2010

us-gaap

Proceeds From Repayments Of Short Term Debt

ProceedsFromRepaymentsOfShortTermDebt

166687000

USD

CY2010

us-gaap

Proceeds From Issuance Of Long Term Debt

ProceedsFromIssuanceOfLongTermDebt

145000000

USD

CY2009

us-gaap

Proceeds From Issuance Or Sale Of Equity

ProceedsFromIssuanceOrSaleOfEquity

383295000

USD

CY2009

us-gaap

Repayments Of Long Term Debt

RepaymentsOfLongTermDebt

54286000

USD

CY2009

us-gaap

Repayments Of Secured Debt

RepaymentsOfSecuredDebt

244075000

USD

CY2009

us-gaap

Proceeds From Payments For Other Financing Activities

ProceedsFromPaymentsForOtherFinancingActivities

-9913000

USD

CY2009

us-gaap

Net Cash Provided By Used In Financing Activities

NetCashProvidedByUsedInFinancingActivities

-149503000

USD

CY2009

us-gaap

Cash And Cash Equivalents Period Increase Decrease

CashAndCashEquivalentsPeriodIncreaseDecrease

-62864000

USD

CY2011Q4

nu

Exchange Ratio For Common Shares Converted As A Result Of Merger

ExchangeRatioForCommonSharesConvertedAsAResultOfMerger

1.312

pure

CY2011Q4

nu

Nu Ownership Post Merger

NuOwnershipPostMerger

0.56

pure

CY2011Q4

nu

Common Shares Issued As A Result Of Merger

CommonSharesIssuedAsAResultOfMerger

137000000

shares

CY2011Q4

nu

Nstar Ownership Post Merger

NstarOwnershipPostMerger

0.44

pure

CY2010Q4

us-gaap

Allowance For Doubtful Accounts Receivable Current

AllowanceForDoubtfulAccountsReceivableCurrent

39800000

USD

CY2011Q4

us-gaap

Allowance For Doubtful Accounts Receivable Current

AllowanceForDoubtfulAccountsReceivableCurrent

34900000

USD

CY2010Q4

nu

Rate Reduction Bond Deposits

RateReductionBondDeposits

53100000

USD

CY2011Q4

nu

Rate Reduction Bond Deposits

RateReductionBondDeposits

29500000

USD

CY2011

nu

Other Deposits

OtherDeposits

17700000

USD

CY2010

nu

Other Deposits

OtherDeposits

29900000

USD

CY2011Q4

us-gaap

Restricted Cash And Cash Equivalents

RestrictedCashAndCashEquivalents

17900000

USD

CY2010Q4

us-gaap

Equity Method Investments

EquityMethodInvestments

2000000

USD

CY2011Q4

us-gaap

Equity Method Investments

EquityMethodInvestments

2100000

USD

CY2011Q4

nu

Schedule21 Nu Wholesale Transmission Revenue Rates Overrecoveryunderrecovery Position

Schedule21NuWholesaleTransmissionRevenueRatesOverrecoveryunderrecoveryPosition

31400000

USD

CY2011Q4

nu

Schedule Of Fuel Costs

ScheduleOfFuelCosts

<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 10px"><td style="width: 190px; text-align:left;border-color:#000000;min-width:190px;"> </td><td colspan="8" style="width: 290px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:290px;">For the Years Ended December 31,</td></tr><tr style="height: 10px"><td style="width: 190px; text-align:left;border-color:#000000;min-width:190px;">(Millions of Dollars)</td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;">2011</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;">2010</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;">2009</td></tr><tr style="height: 10px"><td style="width: 190px; text-align:left;border-color:#000000;min-width:190px;">NU</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"> 307.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"> 391.6</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"> 401.7</td></tr><tr style="height: 9px"><td style="width: 190px; text-align:left;border-color:#000000;min-width:190px;">PSNH</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 115.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 184.3</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 174.1</td></tr><tr style="height: 10px"><td style="width: 190px; text-align:left;border-color:#000000;min-width:190px;">Yankee Gas</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 191.3</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 206.4</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 226.1</td></tr></table></div>

CY2011

nu

Fuel Power Costs

FuelPowerCosts

307900000

USD

CY2010

nu

Fuel Power Costs

FuelPowerCosts

391600000

USD

CY2009

nu

Fuel Power Costs

FuelPowerCosts

401700000

USD

CY2011

us-gaap

Public Utilities Allowance For Funds Used During Construction Capitalized Interest

PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest

-11800000

USD

CY2011

us-gaap

Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity

PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity

22500000

USD

CY2011

nu

Public Utilities Allowance For Funds Used During Construction Capitalized Total

PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedTotal

34300000

USD

CY2010

us-gaap

Public Utilities Allowance For Funds Used During Construction Capitalized Interest

PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest

-10200000

USD

CY2010

us-gaap

Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity

PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity

16700000

USD

CY2010

nu

Public Utilities Allowance For Funds Used During Construction Capitalized Total

PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedTotal

26900000

USD

CY2009

us-gaap

Public Utilities Allowance For Funds Used During Construction Capitalized Interest

PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest

-5900000

USD

CY2009

us-gaap

Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity

PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity

9400000

USD

CY2009

nu

Public Utilities Allowance For Funds Used During Construction Capitalized Total

PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedTotal

15300000

USD

CY2011

us-gaap

Public Utilities Allowance For Funds Used During Construction Rate

PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate

0.073

pure

CY2010

us-gaap

Public Utilities Allowance For Funds Used During Construction Rate

PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate

0.071

pure

CY2009

us-gaap

Public Utilities Allowance For Funds Used During Construction Rate

PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate

0.061

pure

CY2011

us-gaap

Excise And Sales Taxes

ExciseAndSalesTaxes

137800000

USD

CY2010

us-gaap

Excise And Sales Taxes

ExciseAndSalesTaxes

143700000

USD

CY2009

us-gaap

Excise And Sales Taxes

ExciseAndSalesTaxes

135600000

USD

CY2011

us-gaap

Capital Expenditures Incurred But Not Yet Paid

CapitalExpendituresIncurredButNotYetPaid

168500000

USD

CY2010

us-gaap

Capital Expenditures Incurred But Not Yet Paid

CapitalExpendituresIncurredButNotYetPaid

127900000

USD

CY2009

us-gaap

Capital Expenditures Incurred But Not Yet Paid

CapitalExpendituresIncurredButNotYetPaid

125500000

USD

CY2011

us-gaap

Interest Paid Net

InterestPaidNet

256300000

USD

CY2010

us-gaap

Interest Paid Net

InterestPaidNet

258300000

USD

CY2009

us-gaap

Interest Paid Net

InterestPaidNet

263800000

USD

CY2009

us-gaap

Income Taxes Paid Net

IncomeTaxesPaidNet

35100000

USD

CY2010

us-gaap

Income Taxes Paid Net

IncomeTaxesPaidNet

84500000

USD

CY2011

us-gaap

Income Taxes Paid Net

IncomeTaxesPaidNet

-76600000

USD

CY2010

nu

Contributions To Nu Foundation

ContributionsToNuFoundation

2000000

USD

CY2011Q4

us-gaap

Regulatory Assets

RegulatoryAssets

3522800000

USD

CY2010Q4

us-gaap

Regulatory Assets

RegulatoryAssets

2995300000

USD

CY2011

us-gaap

Description Of Regulatory Costs Not Yet Approved

DescriptionOfRegulatoryCostsNotYetApproved

Additionally, the Regulated companies had $32.4 million ($5 million for CL&P, $22.4 million for PSNH, and $1.6 million for WMECO) and $37.5 million ($0.6 million for CL&P, $26.5 million for PSNH, and $1.9 million for WMECO) of regulatory costs as of December 31, 2011 and 2010, respectively, which were included in Other Long-Term Assets on the accompanying consolidated balance sheets. These amounts represent incurred costs that have not yet been approved for recovery by the applicable regulatory agency. Management believes these costs are probable of recovery in future cost-of-service regulated rates. Of the total December 31, 2011 amount, $21.7 million for PSNH related to costs incurred for Tropical Storm Irene and the October snowstorm restorations that met the NHPUC criteria for cost deferral. Refer to the "Storm Cost Deferrals" section below for further discussion.

CY2011

nu

Description Of Regulatory Costs Recently Approved

DescriptionOfRegulatoryCostsRecentlyApproved

The December 31, 2010 balance of regulatory costs included in Other Long-Term Assets at PSNH included costs incurred for the February 2010 wind storm restorations that met the NHPUC specified criteria for cost deferral and certain costs related to previously recognized lost tax benefits as a result of a provision in the 2010 Healthcare Act that eliminated the tax deductibility of actuarially equivalent Medicare Part D benefits for retirees. During June 2011, the NHPUC approved these costs for recovery, with a return on the storm costs, and PSNH recorded a regulatory asset of $10.9 million related to the wind storm restoration costs and $7.2 million for the recovery of the lost tax benefits. On July 28, 2010, PURA allowed the creation by CL&P of a regulatory asset for the recovery of lost tax benefits as a result of the 2010 Healthcare Act, subject to review in its next rate case. On January 31, 2011, the DPU allowed the creation by WMECO of a regulatory asset as a result of the 2010 Healthcare Act. NU has concluded that the costs associated with these lost tax benefits are probable of recovery and as of December 31, 2011, $32.2 million ($18.9 million for CL&P, $6.6 million for PSNH, $3.2 million for WMECO and $3.5 million for Yankee Gas) are included in Other Regulatory Assets in the table above. These assets are not earning a return. PSNH and WMECO's costs are being recovered over a period of 5 to 7 years. For further information regarding the 2010 Healthcare Act, see Note 11, "Income Taxes," to the consolidated financial statements.

CY2011

nu

Description Of Accumulated Equity Return

DescriptionOfAccumulatedEquityReturn

For rate-making purposes, the Regulated companies recover the cost of allowed equity return on certain regulatory assets. This cost, which is not recorded on the accompanying consolidated balance sheets, totaled $3.5 million and $6.1 million for CL&P and $7.6 million and $0.5 million for PSNH as of December 31, 2011 and 2010, respectively. These costs will be recovered in rates.

CY2011

us-gaap

Description Of Regulatory Assets And Liabilities

DescriptionOfRegulatoryAssetsAndLiabilities

Deferred Benefit Costs: NU's Pension, SERP and PBOP Plans are accounted for in accordance with accounting guidance on defined benefit pension and other postretirement plans. Under this accounting guidance, the funded status of pension and other postretirement plans is recorded with an offset to Accumulated Other Comprehensive Income/(Loss) and is remeasured annually. However, because the Regulated companies are rate-regulated on a cost-of-service basis, offsets were recorded as regulatory assets as of December 31, 2011 and 2010 as these amounts have been, and continue to be, recoverable in cost-of-service regulated rates. Regulatory accounting was also applied to the portions of the NUSCO costs that support the Regulated companies, as these amounts are also recoverable. The deferred benefit costs of CL&P and PSNH are not in rate base. WMECO's deferred benefit costs are earning an equity return at the same rate as the assets included in rate base. Pension and PBOP costs are expected to be amortized into expense over the average future employee service period of approximately 10 and 9 years, respectively. Regulatory Assets Offsetting Derivative Liabilities: The regulatory assets offsetting derivative liabilities relate to the fair value of contracts used to purchase power and other related contracts that will be collected from customers in the future. Included in these amounts are derivative liabilities relating to CL&P's capacity contracts, referred to as CfDs. See Note 4, "Derivative Instruments," to the consolidated financial statements for further information.  These assets are excluded from rate base and are being recovered as the actual settlement occurs over the duration of the contracts. Securitized Assets: In April 2001, PSNH issued RRBs in the amount of $525 million. PSNH used the majority of the proceeds from that issuance to buydown its power contracts with an affiliate, North Atlantic Energy Corporation. In May 2001, WMECO issued $155 million in RRBs and used the majority of the proceeds from that issuance to buyout an IPP contract. These assets are not earning an equity return and are being recovered over the amortization period of their associated RRBs. PSNH RRBs are scheduled to fully amortize by May 1, 2013 and WMECO RRBs are scheduled to fully amortize by June 1, 2013. Income Taxes, Net: The tax effect of temporary differences (differences between the periods in which transactions affect income in the financial statements and the periods in which they affect the determination of taxable income, including those differences relating to uncertain tax positions) is accounted for in accordance with the rate-making treatment of the applicable regulatory commissions and accounting guidance for income taxes. Differences in income taxes between the accounting guidance and the rate-making treatment of the applicable regulatory commissions are recorded as regulatory assets. These assets are excluded from rate base. For further information regarding income taxes, see Note 11, "Income Taxes," to the consolidated financial statements. Unrecovered Contractual Obligations: Under the terms of contracts with CYAPC, YAEC and MYAPC, CL&P, PSNH and WMECO are responsible for their proportionate share of the remaining costs of the nuclear facilities, including decommissioning. A portion of these amounts was recorded as unrecovered contractual obligations regulatory assets. These obligations for CL&P are earning a return and are being recovered through the CTA. Amounts for WMECO are being recovered without a return and are anticipated to be recovered by 2013, the scheduled completion date of stranded cost recovery. Amounts for PSNH were fully recovered by 2006. Regulatory Tracker Deferrals: Regulatory tracker deferrals are approved rate mechanisms that allow utilities to recover costs in specific business segments through reconcilable tracking mechanisms that are reviewed at least annually by the applicable regulatory commission. The reconciliation process produces deferrals for future recovery or refund, which can be either under or over-collections to be included in future customer rates each year. Regulatory tracker deferrals are recorded as regulatory assets if costs are in excess of collections from customers and are recorded as regulatory liabilities if collections from customers are in excess of costs. All material regulatory tracker deferrals that are in a regulatory asset position are earning some form of return. The following regulatory tracker deferrals were recorded as either regulatory assets or liabilities as of December 31, 2011 and 2010: CL&P Reconciliation Mechanisms: The PURA has established several reconciliation mechanisms, which allow CL&P to recover costs associated with the procurement of energy for SS and LRS, congestion and other costs associated with power market rules approved by the FERC or as approved by the PURA, C&LM programs, the retail transmission of energy, certain regulatory and energy public policy costs, such as hardship protection costs and transition period property taxes, and stranded costs, such as the amortization of regulatory assets and IPP over market costs. As part of the CTA mechanism reconciliation process, CL&P has also established an obligation to refund the variable incentive portion of its transition service procurement fee, which totaled $26.3 million and $24.7 million as of December 31, 2011 and 2010, respectively, and was recorded as a regulatory liability. PSNH Reconciliation Mechanisms: The NHPUC permits PSNH to recover the costs of providing generation, restructuring costs as a result of deregulation, the retail transmission of energy, and the cost of C&LM programs through various reconciliation mechanisms. WMECO Reconciliation Mechanisms: The DPU has approved a number of individual cost and revenue requirement recovery mechanisms. These mechanisms recover costs associated with providing energy, retail transmission of energy, administrative costs to procure energy, bad debt costs associated with providing energy, company investments in renewable energy, such as solar, and credits given to customers who generate renewable energy. There is also a mechanism for the recovery of stranded generation costs. Additionally, the DPU has provided cost and revenue requirement recovery mechanisms for certain operating expenses. These individual mechanisms include recovery of pension and PBOP costs, certain state government regulatory review, energy efficiency programs, customer arrearage forgiveness programs and low income customer discounts. In the January 31, 2011 rate case, WMECO received approval for a revenue decoupling reconciliation mechanism, which provides assurance that WMECO will recover a DPU pre-established level of baseline distribution delivery service revenue to manage all other distribution operating expenses and earn a level of return on its capital investment. Storm Cost Deferrals: The storm cost deferrals relate to costs incurred at CL&P, PSNH and WMECO for restorations that met regulatory agency specified criteria for cost deferral. On June 1, 2011, a series of severe thunderstorms with high winds, including tornadoes, struck portions of WMECO’s service territory. On June 9, 2011, another series of severe thunderstorms with high winds struck CL&P, PSNH and WMECO's service territories. The cost of restoration that was deferred for future recovery from customers and recorded as a regulatory asset as of December 31, 2011 for CL&P and WMECO totaled $11 million and $3.3 million, respectively. On August 28, 2011, Tropical Storm Irene caused extensive damage to NU’s distribution system. The estimated cost of restoration that was deferred for future recovery from customers and recorded as a regulatory asset as of December 31, 2011 for CL&P and WMECO totaled $105.6 million and $3.2 million, respectively. PSNH recorded $7 million in Other Long-Term Assets as previously described. On October 29, 2011, an unprecedented storm inundated NU’s service territory with heavy snow causing significant damage to NU’s distribution and transmission systems. In terms of customer outages, this was the most severe storm in CL&P’s history, surpassing Tropical Storm Irene; the third most severe in PSNH’s history and the most severe in WMECO's history. The estimated cost of restoration that was deferred for future recovery from customers and recorded as a regulatory asset as of December 31, 2011 for CL&P and WMECO totaled $157.7 million and $23.5 million, respectively. PSNH recorded $14.7 million in Other Long-Term Assets as previously described. The estimated cost of restoration is subject to change as additional cost information becomes available. Management believes its response to the storm damage was prudent and therefore believes it is probable that CL&P, PSNH and WMECO will be allowed to recover these deferred storm costs. CL&P, PSNH and WMECO will seek recovery of these estimated deferred storm costs through the appropriate regulatory recovery process. The PSNH deferral as of December 31, 2011 relates to remaining costs incurred for a major storm in December 2008 and the February 2010 wind storm restorations, both of which were approved for recovery and are included in rate base. WMECO's remaining storm deferral relates to 2008 and 2010 storm costs, which were approved for recovery and are earning a return. Asset Retirement Obligations: The costs associated with the depreciation of the Regulated companies' ARO assets and accretion of the ARO liabilities are recorded as regulatory assets in accordance with regulatory accounting guidance. For CL&P and WMECO, ARO assets, regulatory assets and liabilities offset and are excluded from rate base. PSNH's ARO assets, regulatory assets and liabilities are included in rate base. These costs are being recovered over the life of the underlying property, plant and equipment. Losses on Reacquired Debt: The regulatory asset relates to the losses associated with the reacquisition or redemption of long-term debt and are amortized over the life of the respective long-term debt issuance. These deferred losses are incorporated as part of debt costs included in the rate of return calculation. Deferred Environmental Remediation Costs: This regulatory asset relates to environmental remediation costs at PSNH of $9.7 million and Yankee Gas of $28.8 million. Both PSNH and Yankee Gas have regulatory rate recovery mechanisms for environmental costs and accordingly, offsets to environmental reserves were recorded as regulatory assets. Management continues to believe these costs are probable of recovery in future cost-of-service regulated rates. Deferred Operation and Maintenance Costs: This regulatory asset represents the deferral of maintenance expense in connection with the deferred recovery of revenue requirements for the period July 1, 2010 through December 31, 2010, as allowed by the PURA. CL&P is allowed to recover these costs from January 1, 2011 through June 30, 2012. Cost of Removal: NU's Regulated companies currently recover amounts in rates for future costs of removal of plant assets over the lives of the assets. These amounts are classified as Regulatory Liabilities on the accompanying consolidated balance sheets. Regulatory Liabilities Offsetting Derivative Assets: The regulatory liabilities offsetting derivative assets relate to the fair value of contracts used to purchase power and other related contracts that will benefit customers in the future. See Note 4, "Derivative Instruments," to the consolidated financial statements for further information. This liability is excluded from rate base and is refunded as the actual settlement occurs over the duration of the contracts. AFUDC Transmission Incentive: AFUDC was recorded on 100 percent of CL&P and WMECO's CWIP for their NEEWS projects through May 31, 2011, all of which was reserved as a regulatory liability to reflect rate base recovery for 100 percent of the CWIP as a result of FERC-approved transmission incentives. Effective June 1, 2011, FERC approved changes to the ISO-NE Tariff in order to include 100 percent of the NEEWS CWIP in regional rate base. As a result, CL&P and WMECO no longer record AFUDC on NEEWS CWIP. Overrecovered Spent Nuclear Fuel Costs and Contractual Obligations: CL&P and WMECO currently recover amounts in rates for costs of disposal of spent nuclear fuel and high-level radioactive waste for the period prior to the sale of their ownership shares in the Millstone nuclear power stations. Collections in excess of these costs are recorded as regulatory liabilities. CL&P has also established a regulatory liability for the overrecovery of its proportionate share of the remaining costs, including decommissioning, of the MYAPC nuclear facility. Wholesale Transmission Overcollections: CL&P, PSNH and WMECO's transmission rates recover total transmission revenue requirements, recovering all regional and local revenue requirements for providing transmission service. These rates provide for annual reconciliations to actual costs and the difference between billed and actual costs is deferred. Regulatory liabilities were recorded for collections in excess of costs. Pension Liability - Yankee Gas Acquisition: When Yankee Gas was acquired by NU, the pension liability was adjusted to fair value with an offset to the adjustment recorded as a regulatory liability, as approved by the PURA. The pension liability was approved for amortization over an approximate 13-year period beginning in 2002.

CY2011Q4

us-gaap

Regulatory Liabilities

RegulatoryLiabilities

433900000

USD

CY2010Q4

us-gaap

Regulatory Liabilities

RegulatoryLiabilities

439100000

USD

CY2011Q4

us-gaap

Public Utilities Property Plant And Equipment Distribution

PublicUtilitiesPropertyPlantAndEquipmentDistribution

6540400000

USD

CY2011Q4

nu

Public Utilities Property Plant And Equipment Distribution Natural Gas

PublicUtilitiesPropertyPlantAndEquipmentDistributionNaturalGas

1247600000

USD

CY2011Q4

us-gaap

Public Utilities Property Plant And Equipment Transmission

PublicUtilitiesPropertyPlantAndEquipmentTransmission

3541900000

USD

CY2011Q4

us-gaap

Public Utilities Property Plant And Equipment Generation Or Processing

PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing

1096000000

USD

CY2011Q4

nu

Public Utilities Property Plant And Equipment Electric And Natural Gas Utility Total

PublicUtilitiesPropertyPlantAndEquipmentElectricAndNaturalGasUtilityTotal

12425900000

USD

CY2011Q4

us-gaap

Public Utilities Property Plant And Equipment Other Property Plant And Equipment

PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment

305100000

USD

CY2011Q4

us-gaap

Public Utilities Property Plant And Equipment Plant In Service

PublicUtilitiesPropertyPlantAndEquipmentPlantInService

12731000000

USD

CY2011Q4

nu

Electric And Natural Gas Utility Accumulated Depreciation

ElectricAndNaturalGasUtilityAccumulatedDepreciation

3035500000

USD

CY2011Q4

nu

Other Accumulated Depreciation

OtherAccumulatedDepreciation

120200000

USD

CY2011Q4

us-gaap

Public Utilities Property Plant And Equipment Accumulated Depreciation

PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation

3155700000

USD

CY2011Q4

nu

Property Plant And Equipment Net Excluding Construction Work In Progress

PropertyPlantAndEquipmentNetExcludingConstructionWorkInProgress

9575300000

USD

CY2011Q4

us-gaap

Public Utilities Property Plant And Equipment Construction Work In Progress

PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress

827800000

USD

CY2010Q4

us-gaap

Public Utilities Property Plant And Equipment Distribution

PublicUtilitiesPropertyPlantAndEquipmentDistribution

6197200000

USD

CY2010Q4

nu

Public Utilities Property Plant And Equipment Distribution Natural Gas

PublicUtilitiesPropertyPlantAndEquipmentDistributionNaturalGas

1126600000

USD

CY2010Q4

us-gaap

Public Utilities Property Plant And Equipment Transmission

PublicUtilitiesPropertyPlantAndEquipmentTransmission

3378000000

USD

CY2010Q4

us-gaap

Public Utilities Property Plant And Equipment Generation Or Processing

PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing

697100000

USD

CY2010Q4

nu

Public Utilities Property Plant And Equipment Electric And Natural Gas Utility Total

PublicUtilitiesPropertyPlantAndEquipmentElectricAndNaturalGasUtilityTotal

11398900000

USD

CY2010Q4

us-gaap

Public Utilities Property Plant And Equipment Other Property Plant And Equipment

PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment

305500000

USD

CY2010Q4

us-gaap

Public Utilities Property Plant And Equipment Plant In Service

PublicUtilitiesPropertyPlantAndEquipmentPlantInService

11704400000

USD

CY2010Q4

nu

Electric And Natural Gas Utility Accumulated Depreciation

ElectricAndNaturalGasUtilityAccumulatedDepreciation

2862300000

USD

CY2010Q4

nu

Other Accumulated Depreciation

OtherAccumulatedDepreciation

119900000

USD

CY2010Q4

us-gaap

Public Utilities Property Plant And Equipment Accumulated Depreciation

PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation

2982200000

USD

CY2010Q4

nu

Property Plant And Equipment Net Excluding Construction Work In Progress

PropertyPlantAndEquipmentNetExcludingConstructionWorkInProgress

8722200000

USD

CY2010Q4

us-gaap

Public Utilities Property Plant And Equipment Construction Work In Progress

PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress

845500000

USD

CY2011Q4

nu

Advance Payments On Equipment Purchase Contracts

AdvancePaymentsOnEquipmentPurchaseContracts

15200000

USD

CY2010Q4

nu

Advance Payments On Equipment Purchase Contracts

AdvancePaymentsOnEquipmentPurchaseContracts

9300000

USD

CY2011

nu

Distribution Average Depreciable Lives

DistributionAverageDepreciableLives

38.8

pure

CY2011

nu

Transmission Average Depreciable Lives

TransmissionAverageDepreciableLives

41.2

pure

CY2011

nu

Generation Average Depreciable Lives

GenerationAverageDepreciableLives

29.6

pure

CY2011

nu

Other Average Depreciable Lives

OtherAverageDepreciableLives

17.7

pure

CY2011

nu

Schedule Of Plant Average Depreciable Lives

ScheduleOfPlantAverageDepreciableLives

<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;"> </td><td colspan="11" style="width: 390px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:390px;">Average Depreciable Life</td></tr><tr style="height: 10px"><td colspan="2" style="width: 120px; text-align:left;border-color:#000000;min-width:120px;">(Years)</td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;">NU</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;">CL&P</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;">PSNH</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;">WMECO</td></tr><tr style="height: 10px"><td colspan="2" style="width: 120px; text-align:left;border-color:#000000;min-width:120px;">Distribution</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"> 38.8</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"> 42.1</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"> 33.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"> 29.6</td></tr><tr style="height: 10px"><td colspan="2" style="width: 120px; text-align:left;border-color:#000000;min-width:120px;">Transmission</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 41.2</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 40.6</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 41.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 47.0</td></tr><tr style="height: 10px"><td colspan="2" style="width: 120px; text-align:left;border-color:#000000;min-width:120px;">Generation</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 29.6</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> -</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 29.6</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 25.0</td></tr><tr style="height: 10px"><td colspan="2" style="width: 120px; text-align:left;border-color:#000000;min-width:120px;">Other</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 17.7</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> -</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> -</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> -</td></tr></table></div>

CY2011

us-gaap

Property Plant And Equipment Depreciation Methods

PropertyPlantAndEquipmentDepreciationMethods

The provision for depreciation on utility assets is calculated using the straight-line method based on the estimated remaining useful lives of depreciable plant in-service, adjusted for salvage value and removal costs, as approved by the appropriate regulatory agency (the PURA, NHPUC and the DPU for CL&P, PSNH and WMECO, respectively). Depreciation rates are applied to plant-in-service from the time it is placed in service. When a plant is retired from service, the original cost of the plant is charged to the accumulated provision for depreciation, which includes cost of removal less salvage. Cost of removal is classified as a Regulatory Liability on the accompanying consolidated balance sheets.

CY2011

nu

Schedule Of Plant Depreciation Rates

ScheduleOfPlantDepreciationRates

<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 10px"><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;">(Percent)</td><td colspan="2" style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;">2011</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;">2010</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:90px;">2009</td></tr><tr style="height: 10px"><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;">NU</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"> 2.6</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"> 2.7</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:80px;"> 2.9</td></tr><tr style="height: 10px"><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;">CL&P</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 2.4</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 2.7</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 3.0</td></tr><tr style="height: 10px"><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;">PSNH</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 2.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 2.8</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 2.7</td></tr><tr style="height: 10px"><td style="width: 110px; text-align:left;border-color:#000000;min-width:110px;">WMECO</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 2.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 2.8</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 80px; text-align:right;border-color:#000000;min-width:80px;"> 2.9</td></tr></table></div>

CY2011

nu

Public Utilities Property Plant And Equipment Depreciation Rates

PublicUtilitiesPropertyPlantAndEquipmentDepreciationRates

0.026

pure

CY2010

nu

Public Utilities Property Plant And Equipment Depreciation Rates

PublicUtilitiesPropertyPlantAndEquipmentDepreciationRates

0.027

pure

CY2009

nu

Public Utilities Property Plant And Equipment Depreciation Rates

PublicUtilitiesPropertyPlantAndEquipmentDepreciationRates

0.029

pure

CY2011Q4

nu

Current Derivative Assets Consolidated

CurrentDerivativeAssetsConsolidated

13300000

USD

CY2010Q4

nu

Current Derivative Assets Consolidated

CurrentDerivativeAssetsConsolidated

17300000

USD

CY2011

us-gaap

Description Of Derivative Activity Volume

DescriptionOfDerivativeActivityVolume

As of December 31, 2011 and 2010, NU had approximately 0.1 million and 0.3 million MWh, respectively, of supply volumes remaining in its unregulated wholesale portfolio when expected sales are compared with contracted supply, both of which extend through 2013.

CY2011Q4

nu

Derivative Assets Subject To Credit Risk With Investment Grade Counterparty

DerivativeAssetsSubjectToCreditRiskWithInvestmentGradeCounterparty

102000000

USD

CY2011Q4

us-gaap

Notional Amount Of Fair Value Hedge Instruments

NotionalAmountOfFairValueHedgeInstruments

263000000

USD

CY2010

nu

Interest Realized In Earnings On Fair Value Hedge

InterestRealizedInEarningsOnFairValueHedge

10900000

USD

CY2011

nu

Interest Realized In Earnings On Fair Value Hedge

InterestRealizedInEarningsOnFairValueHedge

10500000

USD

CY2011

us-gaap

Increase Decrease In Fair Value Of Interest Rate Fair Value Hedging Instruments

IncreaseDecreaseInFairValueOfInterestRateFairValueHedgingInstruments

1000000

USD

CY2011

us-gaap

Increase Decrease In Fair Value Of Hedged Item In Interest Rate Fair Value Hedge

IncreaseDecreaseInFairValueOfHedgedItemInInterestRateFairValueHedge

-1000000

USD

CY2010

us-gaap

Increase Decrease In Fair Value Of Hedged Item In Interest Rate Fair Value Hedge

IncreaseDecreaseInFairValueOfHedgedItemInInterestRateFairValueHedge

-9500000

USD

CY2010

us-gaap

Increase Decrease In Fair Value Of Interest Rate Fair Value Hedging Instruments

IncreaseDecreaseInFairValueOfInterestRateFairValueHedgingInstruments

9500000

USD

CY2009

us-gaap

Increase Decrease In Fair Value Of Hedged Item In Interest Rate Fair Value Hedge

IncreaseDecreaseInFairValueOfHedgedItemInInterestRateFairValueHedge

-1600000

USD

CY2009

nu

Interest Realized In Earnings On Fair Value Hedge

InterestRealizedInEarningsOnFairValueHedge

9100000

USD

CY2009

us-gaap

Increase Decrease In Fair Value Of Interest Rate Fair Value Hedging Instruments

IncreaseDecreaseInFairValueOfInterestRateFairValueHedgingInstruments

1600000

USD

CY2011

us-gaap

Cash Flow Hedge Gain Loss Reclassified To Interest Expense Net

CashFlowHedgeGainLossReclassifiedToInterestExpenseNet

-1300000

USD

CY2010

us-gaap

Cash Flow Hedge Gain Loss Reclassified To Interest Expense Net

CashFlowHedgeGainLossReclassifiedToInterestExpenseNet

-400000

USD

CY2011

us-gaap

Other Comprehensive Income Derivatives Qualifying As Hedges Before Tax Period Increase Decrease

OtherComprehensiveIncomeDerivativesQualifyingAsHedgesBeforeTaxPeriodIncreaseDecrease

-25100000

USD

CY2009

us-gaap

Cash Flow Hedge Gain Loss Reclassified To Interest Expense Net

CashFlowHedgeGainLossReclassifiedToInterestExpenseNet

-400000

USD

CY2011Q4

us-gaap

Collateral Already Posted Aggregate Fair Value

CollateralAlreadyPostedAggregateFairValue

4100000

USD

CY2011Q4

us-gaap

Additional Collateral Aggregate Fair Value

AdditionalCollateralAggregateFairValue

19900000

USD

CY2011Q4

nu

Standby Letters Of Credit Posted

StandbyLettersOfCreditPosted

0

USD

CY2011Q4

us-gaap

Derivative Net Liability Position Aggregate Fair Value

DerivativeNetLiabilityPositionAggregateFairValue

23500000

USD

CY2010Q4

us-gaap

Derivative Net Liability Position Aggregate Fair Value

DerivativeNetLiabilityPositionAggregateFairValue

30900000

USD

CY2010Q4

us-gaap

Collateral Already Posted Aggregate Fair Value

CollateralAlreadyPostedAggregateFairValue

500000

USD

CY2010Q4

us-gaap

Additional Collateral Aggregate Fair Value

AdditionalCollateralAggregateFairValue

18500000

USD

CY2010Q4

nu

Standby Letters Of Credit Posted

StandbyLettersOfCreditPosted

24000000

USD

CY2009Q4

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value

FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue

761200000

USD

CY2010Q4

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value

FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue

840200000

USD

CY2011

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings

500000

USD

CY2011

nu

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Gain Loss Included In Reg Asset Liability

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityGainLossIncludedInRegAssetLiability

-161000000

USD

CY2011

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements

38500000

USD

CY2010

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings

2700000

USD

CY2010

nu

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Gain Loss Included In Reg Asset Liability

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityGainLossIncludedInRegAssetLiability

-81200000

USD

CY2010

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements

-500000

USD

CY2011

us-gaap

Fair Value Assets And Liabilities Measured On Recurring Basis Gain Loss Included In Earnings

FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings

700000

USD

CY2010

us-gaap

Fair Value Assets And Liabilities Measured On Recurring Basis Gain Loss Included In Earnings

FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings

1200000

USD

CY2011

nu

Rollforward Of Net Derivative Asset Liabilities Valued Using Unobservable Inputs

RollforwardOfNetDerivativeAssetLiabilitiesValuedUsingUnobservableInputs

<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> </td><td colspan="8" style="width: 320px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:320px;">NU</td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> </td><td colspan="2" style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:100px;">Commodity</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> </td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;">and Capacity</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;">Commodity</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> </td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;">Contracts</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;">Supply and</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> </td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;">Required By</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;"> Price Risk</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> </td><td colspan="2" style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;">Regulation</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;">Management</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;">Total Level 3</td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">(Millions of Dollars)</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">Derivatives, Net: </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 12px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">Fair Value as of January 1, 2010</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> (720.3)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> (40.9)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> (761.2)</td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">Net Realized/Unrealized Gains/(Losses) Included in: </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;">Net Income(1)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> -</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 2.7</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 2.7</td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;">Regulatory Assets/Liabilities</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> (74.0)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> (7.2)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> (81.2)</td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">Settlements</td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> (13.7)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> 13.2</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> (0.5)</td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">Fair Value as of December 31, 2010</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> (808.0)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> (32.2)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> (840.2)</td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">Net Realized/Unrealized Gains/(Losses) Included in: </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;">Net Income(1)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> -</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 0.5</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 0.5</td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;">Regulatory Assets/Liabilities</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> (158.1)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> (2.9)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> (161.0)</td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">Settlements</td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> 26.8</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> 11.7</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> 38.5</td></tr><tr style="height: 9px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">Fair Value as of December 31, 2011</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> (939.3)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> (22.9)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> (962.2)</td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 11px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">Gains Included in Net Income Relating to</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 11px"><td colspan="2" style="width: 285px; text-align:left;border-color:#000000;min-width:285px;">Items Held as of End of Year:</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;">2011</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> -</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 0.7</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 0.7</td></tr><tr style="height: 9px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 275px; text-align:left;border-color:#000000;min-width:275px;">2010</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> -</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 1.2</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 1.2</td></tr></table></div><div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"> </td><td colspan="8" style="width: 260px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:260px;">CL&P</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;">WMECO</td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"> </td><td colspan="2" style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:80px;">Commodity</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:80px;">Commodity</td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;">and Capacity</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;">Commodity</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;">and Capacity</td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;">Contracts</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;">Supply and</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;">Contracts</td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;">Required By</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"> Price Risk</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; text-align:center;border-color:#000000;min-width:80px;">Required By</td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;">(Millions of Dollars)</td><td colspan="2" style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;">Regulation</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;">Management</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;">Total Level 3</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;">Regulation</td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;">Derivatives, Net: </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;">Fair Value as of January 1, 2010</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> (720.3)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> 4.5</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> (715.8)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> -</td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;">Net Realized/Unrealized Losses Included in:</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:left;border-color:#000000;min-width:70px;"> </td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;">Regulatory Assets/Liabilities</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> (74.0)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> (6.2)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> (80.2)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> -</td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;">Settlements</td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> (13.7)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> 3.6</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> (10.1)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> -</td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;">Fair Value as of December 31, 2010</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> (808.0)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> 1.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> (806.1)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> -</td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;">Net Realized/Unrealized Losses Included in:</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:70px;"> </td></tr><tr style="height: 11px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 274px; text-align:left;border-color:#000000;min-width:274px;">Regulatory Assets/Liabilities</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> (150.8)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> (2.8)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> (153.6)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; text-align:right;border-color:#000000;min-width:70px;"> (7.3)</td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;">Settlements</td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> 26.8</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> 1.3</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> 28.1</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 70px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> -</td></tr><tr style="height: 11px"><td colspan="2" style="width: 284px; text-align:left;border-color:#000000;min-width:284px;">Fair Value as of December 31, 2011</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> (932.0)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> 0.4</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> (931.6)</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 70px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:70px;"> (7.3)</td></tr></table></div>

CY2011Q4

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value

FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue

962200000

USD

CY2011Q4

nu

Fair Value Of Securities Under Fair Value Option

FairValueOfSecuritiesUnderFairValueOption

41100000

USD

CY2010Q4

nu

Fair Value Of Securities Under Fair Value Option

FairValueOfSecuritiesUnderFairValueOption

42200000

USD

CY2011

us-gaap

Fair Value Option Changes In Fair Value Gain Loss

FairValueOptionChangesInFairValueGainLoss

-1100000

USD

CY2010

us-gaap

Fair Value Option Changes In Fair Value Gain Loss

FairValueOptionChangesInFairValueGainLoss

6900000

USD

CY2010Q4

us-gaap

Availableforsale Securities Gross Unrealized Gain

AvailableforsaleSecuritiesGrossUnrealizedGain

1300000

USD

CY2011Q4

us-gaap

Availableforsale Securities Gross Unrealized Gain

AvailableforsaleSecuritiesGrossUnrealizedGain

2000000

USD

CY2011Q4

us-gaap

Available For Sale Securities Gross Unrealized Losses1

AvailableForSaleSecuritiesGrossUnrealizedLosses1

-200000

USD

CY2011Q4

us-gaap

Available For Sale Securities Amortized Cost

AvailableForSaleSecuritiesAmortizedCost

88400000

USD

CY2011Q4

us-gaap

Available For Sale Securities Fair Value Disclosure

AvailableForSaleSecuritiesFairValueDisclosure

90200000

USD

CY2010Q4

us-gaap

Available For Sale Securities Amortized Cost

AvailableForSaleSecuritiesAmortizedCost

86300000

USD

CY2010Q4

us-gaap

Available For Sale Securities Fair Value Disclosure

AvailableForSaleSecuritiesFairValueDisclosure

87300000

USD

CY2010Q4

us-gaap

Available For Sale Securities Gross Unrealized Losses1

AvailableForSaleSecuritiesGrossUnrealizedLosses1

-300000

USD

CY2011Q4

us-gaap

Available For Sale Securities Debt Maturities Within One Year Amortized Cost

AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost

29900000

USD

CY2011Q4

us-gaap

Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost

AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost

25400000

USD

CY2011Q4

us-gaap

Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost

AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost

10900000

USD

CY2011Q4

us-gaap

Available For Sale Securities Debt Maturities After Ten Years Amortized Cost

AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost

22200000

USD

CY2011Q4

us-gaap

Available For Sale Securities Debt Maturities Amortized Cost

AvailableForSaleSecuritiesDebtMaturitiesAmortizedCost

88400000

USD

CY2011Q4

us-gaap

Available For Sale Securities Debt Maturities Within One Year Fair Value

AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue

29900000

USD

CY2011Q4

us-gaap

Available For Sale Securities Debt Maturities After One Through Five Years Fair Value

AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue

25600000

USD

CY2011Q4

us-gaap

Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value

AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue

11300000

USD

CY2011Q4

us-gaap

Available For Sale Securities Debt Maturities After Ten Years Fair Value

AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue

23400000

USD

CY2011Q4

us-gaap

Available For Sale Securities Debt Securities

AvailableForSaleSecuritiesDebtSecurities

90200000

USD

CY2011Q4

us-gaap

Investments Fair Value Disclosure

InvestmentsFairValueDisclosure

131300000

USD

CY2010Q4

us-gaap

Investments Fair Value Disclosure

InvestmentsFairValueDisclosure

129500000

USD

CY2010Q4

us-gaap

Asset Retirement Obligation

AssetRetirementObligation

53300000

USD

CY2011

us-gaap

Asset Retirement Obligation Liabilities Incurred

AssetRetirementObligationLiabilitiesIncurred

2100000

USD

CY2011

us-gaap

Asset Retirement Obligation Liabilities Settled

AssetRetirementObligationLiabilitiesSettled

-800000

USD

CY2011

us-gaap

Asset Retirement Obligation Accretion Expense

AssetRetirementObligationAccretionExpense

3500000

USD

CY2011

us-gaap

Asset Retirement Obligation Revision Of Estimate

AssetRetirementObligationRevisionOfEstimate

-1900000

USD

CY2011Q4

us-gaap

Asset Retirement Obligation

AssetRetirementObligation

56200000

USD

CY2009Q4

us-gaap

Asset Retirement Obligation

AssetRetirementObligation

50600000

USD

CY2010

us-gaap

Asset Retirement Obligation Liabilities Incurred

AssetRetirementObligationLiabilitiesIncurred

200000

USD

CY2010

us-gaap

Asset Retirement Obligation Accretion Expense

AssetRetirementObligationAccretionExpense

3300000

USD

CY2010

us-gaap

Asset Retirement Obligation Revision Of Estimate

AssetRetirementObligationRevisionOfEstimate

400000

USD

CY2010

us-gaap

Asset Retirement Obligation Liabilities Settled

AssetRetirementObligationLiabilitiesSettled

-1200000

USD

CY2011

us-gaap

Short Term Debt Terms

ShortTermDebtTerms

CL&P, PSNH, WMECO and Yankee Gas Credit Agreement: On September 24, 2010, CL&P, PSNH, WMECO and Yankee Gas jointly entered into a three-year unsecured revolving credit facility in the amount of $400 million, which terminates on September 24, 2013. CL&P and PSNH may borrow up to $300 million each under this facility, with WMECO and Yankee Gas able to borrow up to $200 million each, subject to the $400 million maximum aggregate borrowing limit. This total commitment may be increased to $500 million at the request of the borrowers, subject to lender approval. Under this facility, each company can borrow either on a short-term or a long-term basis subject to regulatory approval. NU Parent Credit Agreement:  On September 24, 2010, NU parent entered into a three-year unsecured revolving credit facility in the amount of $500 million, which terminates on September 24, 2013. Subject to the amount of advances outstanding, LOCs can be issued under this facility for periods up to 364 days on the account of NU parent or any of its subsidiaries up to the total amount of the facility. This total commitment may be increased to $600 million at the request of NU parent, subject to lender approval. Under this facility, NU parent can borrow either on a short-term or a long-term basis.

CY2011

nu

Short Term Debt Regulatory Limits

ShortTermDebtRegulatoryLimits

:  The amount of short-term borrowings that may be incurred by CL&P and WMECO is subject to periodic approval by the FERC. As a result of the NHPUC having jurisdiction over PSNH's short-term debt, PSNH is not currently required to obtain FERC approval for its short-term borrowings. On November 30, 2011, the FERC granted authorization to allow CL&P and WMECO to incur total short-term borrowings up to a maximum of $450 million and $300 million, respectively, effective January 1, 2012 through December 31, 2013. PSNH is authorized by regulation of the NHPUC to incur short-term borrowings up to 10 percent of net fixed plant. In an order dated December 17, 2010, the NHPUC increased the amount of short-term borrowings authorized for PSNH to a maximum of 10 percent of net fixed plant plus an additional $60 million until further ordered by the NHPUC. As of December 31, 2011, PSNH's short-term debt authorization under the 10 percent of net fixed plant test plus $60 million totaled approximately $270 million. CL&P's certificate of incorporation contains preferred stock provisions restricting the amount of unsecured debt that CL&P may incur, including limiting unsecured indebtedness with a maturity of less than 10 years to 10 percent of total capitalization. In November 2003, CL&P obtained from its preferred stockholders a waiver of such 10 percent limit for a ten-year period expiring in March 2014, provided that all unsecured indebtedness does not exceed 20 percent of total capitalization. As of December 31, 2011, CL&P had $826.3 million of unsecured debt capacity available under this authorization.

CY2011Q4

nu

Letters Of Credit Outstanding Under Line Of Credit

LettersOfCreditOutstandingUnderLineOfCredit

17900000

USD

CY2010Q4

nu

Letters Of Credit Outstanding Under Line Of Credit

LettersOfCreditOutstandingUnderLineOfCredit

32100000

USD

CY2009Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

18.96

CY2011

us-gaap

Long Term Debt Description

LongTermDebtDescription

(1)        On October 24, 2011, CL&P issued $120.5 million of tax-exempt PCRBs carrying a coupon of 4.375 percent that mature on September 1, 2028 and issued $125 million of tax-exempt PCRBs carrying a coupon of 1.25 percent that mature on September 1, 2028 and are subject to mandatory tender for purchase on September 3, 2013. The $125 million of tax-exempt PCRBs were issued with an initial fixed rate term period ending on September 2, 2013, at which time CL&P expects to remarket the PCRBs. The proceeds from these two CL&P issuances were used to refund $245.5 million of PCRBs that carried a coupon of 5.85 percent and had a maturity date of September 1, 2028. (2)        On April 1, 2011, CL&P remarketed the $62 million of tax-exempt PCRBs for a one-year period. The PCRBs, which mature on May 1, 2031, carry a coupon rate of 1.25 percent during the current one-year fixed-rate period and are subject to mandatory tender for purchase on April 1, 2012, at which time CL&P expects to remarket the bonds. (3)        On May 26, 2011, PSNH issued $122 million of first mortgage bonds with a coupon rate of 4.05 percent and a maturity date of June 1, 2021, and used the proceeds to redeem $119.8 million of its tax-exempt 1992 Series D and 1993 Series E PCRBs, each with a maturity date of May 1, 2021 and a coupon rate of 6 percent. The utility plant of CL&P, PSNH and Yankee Gas is subject to the lien of each company's respective first mortgage bond indenture. The CL&P, PSNH and WMECO tax-exempt bonds contain call provisions providing call prices ranging between 100 percent and 102 percent of par. All other long-term debt securities are subject to make-whole provisions. As of December 31, 2011, CL&P had $423.9 million of tax-exempt PCRBs outstanding, $70 million of which is secured by second mortgage liens on transmission assets, junior to the liens of its first mortgage bond indenture. CL&P has $307.5 million of tax-exempt PCRBs secured by first mortgage bonds. If CL&P failed to meet its obligations under the PCRBs, then these first mortgage bonds would become outstanding. As of December 31, 2011, PSNH had $287.5 million in PCRBs outstanding. PSNH's obligation to repay each series of PCRBs is secured by first mortgage bonds and bond insurance. Each such series of first mortgage bonds contains similar terms and provisions as the applicable series of PCRBs. If PSNH failed to meet its obligations under the PCRBs, then these first mortgage bonds would become outstanding. The 2001 Series A PCRBs, in the aggregate principal amount of $89.3 million, bears interest at a rate that is periodically set pursuant to auctions. The Company is not obligated to purchase these PCRBs, which mature in 2021, from the remarketing agent. The weighted average effective interest rate on PSNH's Series A variable-rate PCRBs was 0.21 percent in 2011 and 0.34 percent in 2010. NU's, including CL&P, PSNH and WMECO, long-term debt agreements provide that NU and certain of its subsidiaries must comply with certain financial and non-financial covenants as are customarily included in such agreements, including a consolidated debt to total capitalization ratio. NU and these subsidiaries were in compliance with these covenants as of December 31, 2011. Yankee Gas has certain long-term debt agreements that contain cross-default provisions applicable to all of Yankee Gas’ outstanding first mortgage bond series. The cross-default provisions on Yankee Gas’ Series B Bonds would be triggered if Yankee Gas were to default on a payment due on indebtedness in excess of $2 million. The cross-default provisions on all other series of Yankee Gas’ first mortgage bonds would be triggered if Yankee Gas were to default in a payment due on indebtedness in excess of $10 million. No debt issuances of CL&P, PSNH, WMECO or NU parent contain cross-default provisions as of December 31, 2011. The fair value adjustment relates to the NU parent 7.25 percent note, due 2012 in the amount of $263 million, that is hedged with a fixed to floating interest rate swap. The change in fair value of the interest component of the debt was recorded as an adjustment to Long-Term Debt (Long-Term Debt - Current Portion as of December 31, 2011 since the note was due within one year) with an equal and offsetting adjustment to Derivative Assets for the change in fair value of the fixed to floating interest rate swap. Spent Nuclear Fuel Obligation: Under the Nuclear Waste Policy Act of 1982, CL&P and WMECO must pay the DOE for the costs of disposal of spent nuclear fuel and high-level radioactive waste for the period prior to the sale of their ownership shares in the Millstone nuclear power stations. The DOE is responsible for the selection and development of repositories for, and the disposal of, spent nuclear fuel and high-level radioactive waste. For nuclear fuel used to generate electricity prior to April 7, 1983 (Prior Period Spent Nuclear Fuel) for CL&P and WMECO, an accrual has been recorded for the full liability, and payment must be made by CL&P and WMECO to the DOE prior to the first delivery of spent fuel to the DOE. After the sale of Millstone, CL&P and WMECO remained responsible for their share of the disposal costs associated with the Prior Period Spent Nuclear Fuel. Until such payment to the DOE is made, the outstanding liability will continue to accrue interest at the 3-month Treasury bill yield rate. Fees due to the DOE for the disposal of Prior Period Spent Nuclear Fuel as of December 31, 2011 and 2010 are included in Long-Term Debt, including accumulated interest costs of $219.3 million and $218.9 million ($177.6 million and $177.3 million for CL&P and $41.7 million and $41.6 million for WMECO), respectively. WMECO maintains a trust that holds marketable securities to fund amounts due to the DOE for the disposal of WMECO's Prior Period Spent Nuclear Fuel. For further information on this trust, see Note 5, "Marketable Securities," to the consolidated financial statements.

CY2011Q4

us-gaap

Long Term Debt Maturities Repayments Of Principal In Next Twelve Months

LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths

329300000

USD

CY2011Q4

us-gaap

Long Term Debt Maturities Repayments Of Principal In Year Two

LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo

430000000

USD

CY2011Q4

us-gaap

Long Term Debt Maturities Repayments Of Principal In Year Three

LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree

275000000

USD

CY2011Q4

us-gaap

Long Term Debt Maturities Repayments Of Principal In Year Four

LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour

150000000

USD

CY2011Q4

us-gaap

Long Term Debt Maturities Repayments Of Principal In Year Five

LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive

15400000

USD

CY2011Q4

us-gaap

Long Term Debt Maturities Repayments Of Principal After Year Five

LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive

3449600000

USD

CY2011Q4

nu

Longtermdebtmaturitiesrepaymentsofprincipaltotal

4649300000

USD

CY2011Q4

nu

Defined Benefit Plan Benefits Paid Lump Sum

DefinedBenefitPlanBenefitsPaidLumpSum

0

USD

CY2011

us-gaap

Defined Benefit Plan Estimated Future Employer Contributions In Next Fiscal Year Description

DefinedBenefitPlanEstimatedFutureEmployerContributionsInNextFiscalYearDescription

A contribution of $143.6 million ($112.6 million of which was contributed by PSNH) was made in 2011. Based on the current status of the Pension Plan, NU is required to make a contribution to the Pension Plan of approximately $197.3 million in 2012, which will be made in quarterly installments, to meet minimum current funding requirements under the PPA.

CY2011

nu

Schedule Of Defined Contribution Plans401k

ScheduleOfDefinedContributionPlans401k

<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;">(Millions of Dollars)</td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">NU</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">CL&P</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">PSNH</td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">WMECO</td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;">2011</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;">13.2</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;">4.0</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;">2.5</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;">0.8</td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;">2010</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"> 12.7</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">4.0</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">2.4</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">0.8</td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;">2009</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"> 12.2</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">3.9</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">2.3</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">0.7</td></tr></table></div>

CY2011

nu

Schedule Of Defined Contribution Plans K Vantage

ScheduleOfDefinedContributionPlansKVantage

<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;">(Millions of Dollars)</td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">NU</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">CL&P</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">PSNH</td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 74px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:74px;">WMECO</td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;">2011</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;">4.2</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;">0.5</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;">0.6</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 64px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:64px;">0.1</td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;">2010</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"> 3.4</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">0.4</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">0.4</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">0.1</td></tr><tr style="height: 11px"><td style="width: 224px; text-align:left;border-color:#000000;min-width:224px;">2009</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"> 2.6</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">0.2</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;">0.3</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 64px; text-align:right;border-color:#000000;min-width:64px;"> -</td></tr></table></div>

CY2011

us-gaap

Employee Stock Ownership Plan Esop Debt Structure Employer Loan Description

EmployeeStockOwnershipPlanESOPDebtStructureEmployerLoanDescription

NU issued unsecured notes during 1991 and 1992 totaling $250 million, the proceeds of which were loaned to the ESOP trust (ESOP Notes) for the purchase of 10.8 million newly issued NU common shares (ESOP shares). During 2010, the ESOP Notes were fully repaid and all ESOP shares purchased with the proceeds of the ESOP Notes were fully allocated. As of December 31, 2011 and 2010, total allocated ESOP shares were 10,800,185. Following complete allocation of the ESOP shares, continuing allocations of NU common shares were made from NU treasury shares to satisfy the 401(k) Savings Plan obligation to provide a portion of the matching contribution in NU common shares.

CY2010

us-gaap

Employee Stock Ownership Plan Esop Cash Contributions To Esop

EmployeeStockOwnershipPlanESOPCashContributionsToESOP

1100000

USD

CY2009

us-gaap

Employee Stock Ownership Plan Esop Cash Contributions To Esop

EmployeeStockOwnershipPlanESOPCashContributionsToESOP

6100000

USD

CY2011

us-gaap

Employee Stock Ownership Plan Esop Compensation Expense

EmployeeStockOwnershipPlanESOPCompensationExpense

8800000

USD

CY2010

us-gaap

Employee Stock Ownership Plan Esop Compensation Expense

EmployeeStockOwnershipPlanESOPCompensationExpense

8500000

USD

CY2009

us-gaap

Employee Stock Ownership Plan Esop Compensation Expense

EmployeeStockOwnershipPlanESOPCompensationExpense

8200000

USD

CY2010Q4

us-gaap

Employee Stock Ownership Plan Esop Number Of Allocated Shares

EmployeeStockOwnershipPlanESOPNumberOfAllocatedShares

127054

shares

CY2010Q4

nu

Employee Stock Ownership Plan Esop Numberof Allocated Shares In Total

EmployeeStockOwnershipPlanESOPNumberofAllocatedSharesInTotal

10800185

shares

CY2011Q4

nu

Employee Stock Ownership Plan Esop Numberof Allocated Shares In Total

EmployeeStockOwnershipPlanESOPNumberofAllocatedSharesInTotal

10800185

shares

CY2011

us-gaap

Employee Stock Ownership Plan Esop Dividends Paid To Esop

EmployeeStockOwnershipPlanESOPDividendsPaidToESOP

0.275

USD

CY2010

us-gaap

Employee Stock Ownership Plan Esop Dividends Paid To Esop

EmployeeStockOwnershipPlanESOPDividendsPaidToESOP

0.25625

USD

CY2009

us-gaap

Employee Stock Ownership Plan Esop Dividends Paid To Esop

EmployeeStockOwnershipPlanESOPDividendsPaidToESOP

0.2375

USD

CY2011

us-gaap

Excess Tax Benefit From Share Based Compensation Financing Activities

ExcessTaxBenefitFromShareBasedCompensationFinancingActivities

1300000

USD

CY2010

us-gaap

Excess Tax Benefit From Share Based Compensation Financing Activities

ExcessTaxBenefitFromShareBasedCompensationFinancingActivities

900000

USD

CY2009

us-gaap

Excess Tax Benefit From Share Based Compensation Financing Activities

ExcessTaxBenefitFromShareBasedCompensationFinancingActivities

900000

USD

CY2011Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized

ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized

4500000

shares

CY2011Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant

ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant

2685615

shares

CY2010Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant

ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant

3068850

shares

CY2011

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Compensation Cost

ShareBasedCompensationArrangementByShareBasedPaymentAwardCompensationCost

12300000

USD

CY2010

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Compensation Cost

ShareBasedCompensationArrangementByShareBasedPaymentAwardCompensationCost

10500000

USD

CY2009

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Compensation Cost

ShareBasedCompensationArrangementByShareBasedPaymentAwardCompensationCost

8800000

USD

CY2011

us-gaap

Employee Service Share Based Compensation Tax Benefit From Compensation Expense

EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense

4900000

USD

CY2010

us-gaap

Employee Service Share Based Compensation Tax Benefit From Compensation Expense

EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense

4200000

USD

CY2009

us-gaap

Employee Service Share Based Compensation Tax Benefit From Compensation Expense

EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense

3500000

USD

CY2011Q4

us-gaap

Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized

EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized

8900000

USD

CY2011

us-gaap

Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition

EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition

1.77

pure

CY2011Q4

us-gaap

Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term1

SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm1

0.3

pure

CY2008Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber

320920

shares

CY2009

us-gaap

Stock Issued During Period Shares Stock Options Exercised

StockIssuedDuringPeriodSharesStockOptionsExercised

-95704

shares

CY2009

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod

0

shares

CY2009Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber

225216

shares

CY2010

us-gaap

Stock Issued During Period Shares Stock Options Exercised

StockIssuedDuringPeriodSharesStockOptionsExercised

-112617

shares

CY2010

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod

0

shares

CY2010Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber

112599

shares

CY2011

us-gaap

Stock Issued During Period Shares Stock Options Exercised

StockIssuedDuringPeriodSharesStockOptionsExercised

-65225

shares

CY2011

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod

0

shares

CY2011Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber

47374

shares

CY2008

us-gaap

Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Lower Range Limit

ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit

14.94

CY2009

us-gaap

Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Lower Range Limit

ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit

17.40

CY2010

us-gaap

Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Lower Range Limit

ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit

17.40

CY2011

us-gaap

Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Lower Range Limit

ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit

18.58

CY2008

us-gaap

Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Upper Range Limit

ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit

21.03

CY2009

us-gaap

Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Upper Range Limit

ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit

21.03

CY2010

us-gaap

Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Upper Range Limit

ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit

21.03

CY2011

us-gaap

Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Upper Range Limit

ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit

18.90

CY2008Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

18.83

CY2011Q4

nu

Employee Stock Purchase Plan Shares Remaining For Future Issuance

EmployeeStockPurchasePlanSharesRemainingForFutureIssuance

896702

shares

CY2010Q4

nu

Employee Stock Purchase Plan Shares Remaining For Future Issuance

EmployeeStockPurchasePlanSharesRemainingForFutureIssuance

932178

shares

CY2011

nu

Espp Discounted Purchase Price First Six Months

ESPPDiscountedPurchasePriceFirstSixMonths

31.27

USD

CY2011

nu

Espp Discounted Purchase Price Second Six Months

ESPPDiscountedPurchasePriceSecondSixMonths

32.30

USD

CY2010

nu

Espp Discounted Purchase Price First Six Months

ESPPDiscountedPurchasePriceFirstSixMonths

26.45

USD

CY2010Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

18.80

CY2011Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

18.78

CY2009Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice

18.54

CY2010Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice

19.12

CY2011Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice

18.81

CY2009

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice

0

CY2010

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice

0

CY2011

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice

0

CY2009

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue

600000

USD

CY2010

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue

1000000

USD

CY2011

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue

1000000

USD

CY2011Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue

800000

USD

CY2011

us-gaap

Employee Service Share Based Compensation Cash Received From Exercise Of Stock Options

EmployeeServiceShareBasedCompensationCashReceivedFromExerciseOfStockOptions

1200000

USD

CY2011

us-gaap

Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Options

EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOptions

400000

USD

CY2011

us-gaap

Stock Issued During Period Shares Employee Stock Purchase Plans

StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans

35476

shares

CY2010

nu

Espp Discounted Purchase Price Second Six Months

ESPPDiscountedPurchasePriceSecondSixMonths

24.05

USD

CY2010

us-gaap

Stock Issued During Period Shares Employee Stock Purchase Plans

StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans

38672

shares

CY2011Q4

us-gaap

Deferred Compensation Cashbased Arrangements Liability Classified Noncurrent

DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent

52800000

USD

CY2010Q4

us-gaap

Deferred Compensation Cashbased Arrangements Liability Classified Noncurrent

DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent

49900000

USD

CY2009Q4

us-gaap

Deferred Compensation Cashbased Arrangements Liability Classified Noncurrent

DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent

47900000

USD

CY2011Q4

nu

Deferred Compensation Cash Based Arrangements Expense Pertaining To Deferred Benefits

DeferredCompensationCashBasedArrangementsExpensePertainingToDeferredBenefits

4700000

USD

CY2010Q4

nu

Deferred Compensation Cash Based Arrangements Expense Pertaining To Deferred Benefits

DeferredCompensationCashBasedArrangementsExpensePertainingToDeferredBenefits

4200000

USD

CY2009Q4

nu

Deferred Compensation Cash Based Arrangements Expense Pertaining To Deferred Benefits

DeferredCompensationCashBasedArrangementsExpensePertainingToDeferredBenefits

3900000

USD

CY2011

us-gaap

Current Federal Tax Expense Benefit

CurrentFederalTaxExpenseBenefit

3000000

USD

CY2010

us-gaap

Current Federal Tax Expense Benefit

CurrentFederalTaxExpenseBenefit

9000000

USD

CY2009

us-gaap

Current Federal Tax Expense Benefit

CurrentFederalTaxExpenseBenefit

4500000

USD

CY2009

us-gaap

Current State And Local Tax Expense Benefit

CurrentStateAndLocalTaxExpenseBenefit

52700000

USD

CY2010

us-gaap

Current State And Local Tax Expense Benefit

CurrentStateAndLocalTaxExpenseBenefit

-6500000

USD

CY2011

us-gaap

Current State And Local Tax Expense Benefit

CurrentStateAndLocalTaxExpenseBenefit

-26000000

USD

CY2011

us-gaap

Current Income Tax Expense Benefit

CurrentIncomeTaxExpenseBenefit

-23000000

USD

CY2010

us-gaap

Current Income Tax Expense Benefit

CurrentIncomeTaxExpenseBenefit

2500000

USD

CY2009

us-gaap

Current Income Tax Expense Benefit

CurrentIncomeTaxExpenseBenefit

57200000

USD

CY2009

us-gaap

Deferred Federal Income Tax Expense Benefit

DeferredFederalIncomeTaxExpenseBenefit

155100000

USD

CY2010

us-gaap

Deferred Federal Income Tax Expense Benefit

DeferredFederalIncomeTaxExpenseBenefit

201200000

USD

CY2011

us-gaap

Deferred Federal Income Tax Expense Benefit

DeferredFederalIncomeTaxExpenseBenefit

187700000

USD

CY2011

us-gaap

Deferred State And Local Income Tax Expense Benefit

DeferredStateAndLocalIncomeTaxExpenseBenefit

9100000

USD

CY2010

us-gaap

Deferred State And Local Income Tax Expense Benefit

DeferredStateAndLocalIncomeTaxExpenseBenefit

9700000

USD

CY2009

us-gaap

Deferred State And Local Income Tax Expense Benefit

DeferredStateAndLocalIncomeTaxExpenseBenefit

-29200000

USD

CY2009

us-gaap

Income Tax Reconciliation Tax Credits Investment

IncomeTaxReconciliationTaxCreditsInvestment

-3200000

USD

CY2010

us-gaap

Income Tax Reconciliation Tax Credits Investment

IncomeTaxReconciliationTaxCreditsInvestment

-3000000

USD

CY2011

us-gaap

Income Tax Reconciliation Tax Credits Investment

IncomeTaxReconciliationTaxCreditsInvestment

-2800000

USD

CY2011

us-gaap

Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate

IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate

200000000

USD

CY2011

us-gaap

Income Tax Reconciliation Nondeductible Expense Depreciation

IncomeTaxReconciliationNondeductibleExpenseDepreciation

-14200000

USD

CY2011

us-gaap

Income Tax Reconciliation Tax Credits Other

IncomeTaxReconciliationTaxCreditsOther

-3500000

USD

CY2011

us-gaap

Income Tax Reconciliation State And Local Income Taxes

IncomeTaxReconciliationStateAndLocalIncomeTaxes

22100000

USD

CY2011

nu

Medicare Subsidy

MedicareSubsidy

0

USD

CY2011

us-gaap

Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance

IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance

-33100000

USD

CY2011

us-gaap

Income Tax Reconciliation Other Adjustments

IncomeTaxReconciliationOtherAdjustments

2500000

USD

CY2010

us-gaap

Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate

IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate

211600000

USD

CY2010

us-gaap

Income Tax Reconciliation Nondeductible Expense Depreciation

IncomeTaxReconciliationNondeductibleExpenseDepreciation

-9500000

USD

CY2010

us-gaap

Income Tax Reconciliation Tax Credits Other

IncomeTaxReconciliationTaxCreditsOther

-3800000

USD

CY2010

us-gaap

Income Tax Reconciliation State And Local Income Taxes

IncomeTaxReconciliationStateAndLocalIncomeTaxes

12500000

USD

CY2010

nu

Medicare Subsidy

MedicareSubsidy

15600000

USD

CY2010

us-gaap

Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance

IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance

-10500000

USD

CY2010

us-gaap

Income Tax Reconciliation Other Adjustments

IncomeTaxReconciliationOtherAdjustments

-2500000

USD

CY2009

us-gaap

Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate

IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate

180400000

USD

CY2009

us-gaap

Income Tax Reconciliation Nondeductible Expense Depreciation

IncomeTaxReconciliationNondeductibleExpenseDepreciation

-2700000

USD

CY2009

us-gaap

Income Tax Reconciliation Tax Credits Other

IncomeTaxReconciliationTaxCreditsOther

-3800000

USD

CY2009

us-gaap

Income Tax Reconciliation State And Local Income Taxes

IncomeTaxReconciliationStateAndLocalIncomeTaxes

11500000

USD

CY2009

nu

Medicare Subsidy

MedicareSubsidy

-3500000

USD

CY2009

us-gaap

Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance

IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance

3800000

USD

CY2009

us-gaap

Income Tax Reconciliation Other Adjustments

IncomeTaxReconciliationOtherAdjustments

-2600000

USD

CY2011

us-gaap

Effective Income Tax Rate Continuing Operations

EffectiveIncomeTaxRateContinuingOperations

0.299

pure

CY2010

us-gaap

Effective Income Tax Rate Continuing Operations

EffectiveIncomeTaxRateContinuingOperations

0.348

pure

CY2009

us-gaap

Effective Income Tax Rate Continuing Operations

EffectiveIncomeTaxRateContinuingOperations

0.349

pure

CY2011Q4

us-gaap

Deferred Tax Assets Derivative Instruments

DeferredTaxAssetsDerivativeInstruments

415300000

USD

CY2010Q4

us-gaap

Deferred Tax Assets Derivative Instruments

DeferredTaxAssetsDerivativeInstruments

376500000

USD

CY2011Q4

us-gaap

Deferred Tax Assets Regulatory Assets And Liabilities

DeferredTaxAssetsRegulatoryAssetsAndLiabilities

157900000

USD

CY2010Q4

us-gaap

Deferred Tax Assets Regulatory Assets And Liabilities

DeferredTaxAssetsRegulatoryAssetsAndLiabilities

135500000

USD

CY2011Q4

nu

Deferred Tax Assets Employee Benefits

DeferredTaxAssetsEmployeeBenefits

539600000

USD

CY2010Q4

nu

Deferred Tax Assets Employee Benefits

DeferredTaxAssetsEmployeeBenefits

470100000

USD

CY2010Q4

nu

Deferred Tax Assets Tax Effect Tax Regulatory Assets

DeferredTaxAssetsTaxEffectTaxRegulatoryAssets

17000000

USD

CY2011Q4

nu

Deferred Tax Assets Tax Effect Tax Regulatory Assets

DeferredTaxAssetsTaxEffectTaxRegulatoryAssets

15500000

USD

CY2010

us-gaap

Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations

UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations

-400000

USD

CY2011Q4

us-gaap

Deferred Tax Assets Other

DeferredTaxAssetsOther

204200000

USD

CY2010Q4

us-gaap

Deferred Tax Assets Other

DeferredTaxAssetsOther

188000000

USD

CY2011Q4

us-gaap

Deferred Tax Assets Valuation Allowance

DeferredTaxAssetsValuationAllowance

4600000

USD

CY2010Q4

us-gaap

Deferred Tax Assets Valuation Allowance

DeferredTaxAssetsValuationAllowance

19800000

USD

CY2010Q4

us-gaap

Deferred Tax Assets Net

DeferredTaxAssetsNet

1213700000

USD

CY2011Q4

us-gaap

Deferred Tax Assets Net

DeferredTaxAssetsNet

1551900000

USD

CY2011Q4

us-gaap

Deferred Tax Liabilities Property Plant And Equipment

DeferredTaxLiabilitiesPropertyPlantAndEquipment

1920500000

USD

CY2010Q4

nu

Deferred Tax Liabilities Regulatory Assets Securitized Contract Termination Costs

DeferredTaxLiabilitiesRegulatoryAssetsSecuritizedContractTerminationCosts

65800000

USD

CY2011Q4

nu

Deferred Tax Liabilities Regulatory Assets Securitized Contract Termination Costs

DeferredTaxLiabilitiesRegulatoryAssetsSecuritizedContractTerminationCosts

39600000

USD

CY2011Q4

nu

Deferred Tax Liabilities Regulatory Assets Other Regulatory Deferrals

DeferredTaxLiabilitiesRegulatoryAssetsOtherRegulatoryDeferrals

1135000000

USD

CY2010Q4

nu

Deferred Tax Liabilities Regulatory Assets Other Regulatory Deferrals

DeferredTaxLiabilitiesRegulatoryAssetsOtherRegulatoryDeferrals

873300000

USD

CY2010Q4

nu

Deferred Tax Liabilities Regulatory Assets Tax Effect Tax Regulatory Assets

DeferredTaxLiabilitiesRegulatoryAssetsTaxEffectTaxRegulatoryAssets

177100000

USD

CY2011Q4

nu

Deferred Tax Liabilities Regulatory Assets Tax Effect Tax Regulatory Assets

DeferredTaxLiabilitiesRegulatoryAssetsTaxEffectTaxRegulatoryAssets

184600000

USD

CY2011Q4

nu

Deferred Tax Liabilities Regulatory Assets Derivative Assets

DeferredTaxLiabilitiesRegulatoryAssetsDerivativeAssets

39100000

USD

CY2010Q4

nu

Deferred Tax Liabilities Regulatory Assets Derivative Assets

DeferredTaxLiabilitiesRegulatoryAssetsDerivativeAssets

48000000

USD

CY2010Q4

us-gaap

Deferred Tax Liabilities Other

DeferredTaxLiabilitiesOther

26300000

USD

CY2011Q4

us-gaap

Deferred Tax Liabilities Other

DeferredTaxLiabilitiesOther

24500000

USD

CY2011Q4

us-gaap

Deferred Tax Liabilities

DeferredTaxLiabilities

3402200000

USD

CY2010Q4

us-gaap

Deferred Tax Liabilities

DeferredTaxLiabilities

2858200000

USD

CY2011Q4

us-gaap

Deferred Tax Assets Gross

DeferredTaxAssetsGross

1556500000

USD

CY2010Q4

us-gaap

Deferred Tax Assets Gross

DeferredTaxAssetsGross

1233500000

USD

CY2011Q4

us-gaap

Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts

DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts

45400000

USD

CY2010Q4

us-gaap

Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts

DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts

46400000

USD

CY2011Q4

nu

Deferred Tax Liabilities Resulting From Property Tax Accruals And Other

DeferredTaxLiabilitiesResultingFromPropertyTaxAccrualsAndOther

58900000

USD

CY2010Q4

nu

Deferred Tax Liabilities Resulting From Property Tax Accruals And Other

DeferredTaxLiabilitiesResultingFromPropertyTaxAccrualsAndOther

55100000

USD

CY2010Q4

us-gaap

Deferred Tax Liabilities Property Plant And Equipment

DeferredTaxLiabilitiesPropertyPlantAndEquipment

1612600000

USD

CY2011Q4

us-gaap

Deferred Tax Assets Operating Loss Carryforwards

DeferredTaxAssetsOperatingLossCarryforwards

178600000

USD

CY2010Q4

us-gaap

Deferred Tax Assets Operating Loss Carryforwards

DeferredTaxAssetsOperatingLossCarryforwards

0

USD

CY2011

us-gaap

Operating Loss Carryforwards Expiration Dates

OperatingLossCarryforwardsExpirationDates

As of December 31, 2011, NU had state credit carryforwards of $101.4 million that begin expiring in 2013. NU’s state net operating loss carryforward as of December 31, 2011 was not significant. As of December 31, 2010, NU had state net operating loss carryforwards of $317.7 million that expire between December 31, 2011 and December 31, 2027 and state credit carryforwards of $84.9 million that begin expiring in 2013. The state net operating loss carryforward deferred tax asset has been fully reserved by a valuation allowance. As of December 31, 2011, NU had a federal net operating loss carryforward of $510.2 million and federal credit carryforwards of $6.6 million that expire December 31, 2031.

CY2011

us-gaap

Tax Credit Carryforward Expiration Dates

TaxCreditCarryforwardExpirationDates

As of December 31, 2011, NU had state credit carryforwards of $101.4 million that begin expiring in 2013. NU’s state net operating loss carryforward as of December 31, 2011 was not significant. As of December 31, 2010, NU had state net operating loss carryforwards of $317.7 million that expire between December 31, 2011 and December 31, 2027 and state credit carryforwards of $84.9 million that begin expiring in 2013. The state net operating loss carryforward deferred tax asset has been fully reserved by a valuation allowance. As of December 31, 2011, NU had a federal net operating loss carryforward of $510.2 million and federal credit carryforwards of $6.6 million that expire December 31, 2031.

CY2008Q4

us-gaap

Unrecognized Tax Benefits

UnrecognizedTaxBenefits

156300000

USD

CY2009

us-gaap

Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions

UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions

12300000

USD

CY2009

us-gaap

Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities

UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities

-44200000

USD

CY2009

us-gaap

Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations

UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations

-100000

USD

CY2009Q4

us-gaap

Unrecognized Tax Benefits

UnrecognizedTaxBenefits

124300000

USD

CY2010

us-gaap

Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions

UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions

10800000

USD

CY2010

us-gaap

Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions

UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions

800000

USD

CY2010

us-gaap

Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities

UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities

-34300000

USD

CY2010Q4

us-gaap

Unrecognized Tax Benefits

UnrecognizedTaxBenefits

101200000

USD

CY2011

us-gaap

Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions

UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions

8000000

USD

CY2011Q4

us-gaap

Unrecognized Tax Benefits

UnrecognizedTaxBenefits

73500000

USD

CY2011

us-gaap

Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions

UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions

-35700000

USD

CY2011

us-gaap

Unrecognized Tax Benefits Interest On Income Taxes Expense

UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense

-2800000

USD

CY2010

us-gaap

Unrecognized Tax Benefits Interest On Income Taxes Expense

UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense

-24800000

USD

CY2009

us-gaap

Unrecognized Tax Benefits Interest On Income Taxes Expense

UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense

-4000000

USD

CY2011Q4

us-gaap

Unrecognized Tax Benefits Interest On Income Taxes Accrued

UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued

7100000

USD

CY2010Q4

us-gaap

Unrecognized Tax Benefits Interest On Income Taxes Accrued

UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued

9900000

USD

CY2011

us-gaap

Tax Adjustments Settlements And Unusual Provisions

TaxAdjustmentsSettlementsAndUnusualProvisions

29100000

USD

CY2011Q4

us-gaap

Significant Change In Unrecognized Tax Benefits Is Reasonably Possible Estimated Range Of Change Upper Bound

SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleEstimatedRangeOfChangeUpperBound

50000000

USD

CY2011

nu

Impact Of The2010 Healthcare Act

ImpactOfThe2010HealthcareAct

On March 23, 2010, President Obama signed into law the 2010 Healthcare Act. The 2010 Healthcare Act was amended by a Reconciliation Bill signed into law on March 30, 2010. The 2010 Healthcare Act includes a provision that eliminated the tax deductibility of certain PBOP contributions for retiree prescription drug benefits. The tax deduction eliminated by this legislation represented a loss of previously recognized deferred income tax assets established through 2009 and as a result, these assets were written down by approximately $18 million in 2010. Since the electric and natural gas distribution companies are cost-of-service and rate-regulated, and approximately $15 million of the $18 million is able to be deferred and recovered through future rates, NU reduced 2010 earnings by $3 million of non-recoverable costs. In addition, as a result of the elimination of the tax deduction in 2010, NU was not able to recognize approximately $2 million of net annual benefits

CY2011

nu

Impact Of The Small Business Jobs And Credit Act Of2010

ImpactOfTheSmallBusinessJobsAndCreditActOf2010

On September 27, 2010, President Obama signed into law the Small Business Jobs and Credit Act of 2010, which extends the bonus depreciation provisions of the American Recovery and Reinvestment Act of 2009 to small and large businesses through 2010. This extended stimulus provided NU with cash flow benefits of approximately $100 million.

CY2011

nu

Impact Of The2010 Tax Act

ImpactOfThe2010TaxAct

On December 17, 2010, President Obama signed into law the Tax Relief, Unemployment Insurance Reauthorization and Job Creation Act (2010 Tax Act), which, among other things, provides 100 percent bonus depreciation for tangible personal property placed in service after September 8, 2010, and through December 31, 2011. For tangible personal property placed in service after December 31, 2011, and through December 31, 2012, the 2010 Tax Act provides for 50 percent bonus depreciation.

CY2011

us-gaap

Significant Change In Unrecognized Tax Benefits Is Reasonably Possible Other Information

SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleOtherInformation

These estimated changes could have an impact on NU's and CL&P's 2012 earnings of zero to $32 million and zero to $26 million, respectively.  Other companies’ impacts are not expected to be material.

CY2009Q4

us-gaap

Accrual For Environmental Loss Contingencies

AccrualForEnvironmentalLossContingencies

26000000

USD

CY2010

us-gaap

Accrual For Environmental Loss Contingencies Provision For New Losses

AccrualForEnvironmentalLossContingenciesProvisionForNewLosses

18200000

USD

CY2010

us-gaap

Accrual For Environmental Loss Contingencies Payments

AccrualForEnvironmentalLossContingenciesPayments

7100000

USD

CY2010Q4

us-gaap

Accrual For Environmental Loss Contingencies

AccrualForEnvironmentalLossContingencies

37100000

USD

CY2011

us-gaap

Accrual For Environmental Loss Contingencies Provision For New Losses

AccrualForEnvironmentalLossContingenciesProvisionForNewLosses

1600000

USD

CY2011

us-gaap

Accrual For Environmental Loss Contingencies Payments

AccrualForEnvironmentalLossContingenciesPayments

7000000

USD

CY2011Q4

us-gaap

Accrual For Environmental Loss Contingencies

AccrualForEnvironmentalLossContingencies

31700000

USD

CY2011

nu

Environmental Site Quantity

EnvironmentalSiteQuantity

59

pure

CY2010

nu

Environmental Site Quantity

EnvironmentalSiteQuantity

58

pure

CY2011Q4

us-gaap

Accrual For Environmental Loss Contingencies Component Amount

AccrualForEnvironmentalLossContingenciesComponentAmount

2400000

USD

CY2011

nu

Cumulative Environmental Remediation Expense

CumulativeEnvironmentalRemediationExpense

19500000

USD

CY2011Q4

nu

Range Of Potential Loss On Enivornmental Sites

RangeOfPotentialLossOnEnivornmentalSites

MGP sites are sites that were operated several decades ago and produced manufacturing gas from coal, which resulted in certain byproducts in the environment that may pose a risk to human health and the environment. As of December 31, 2011, for 5 environmental sites (2 for PSNH and 1 for WMECO) that are included in the Company's reserve for environmental costs, the information known and nature of the remediation options at those sites allow for the Company to estimate the range of losses for environmental costs. As of December 31, 2011, $4.9 million ($0.7 million for PSNH) had been accrued as a liability for these sites, which represent management's best estimates of the liabilities for environmental costs. These amounts are the best estimates within estimated ranges of losses from $1.3 million to $16.8 million (zero to $4.1 million for PSNH and zero to $8.6 million for WMECO). For the sites that comprise the remaining $26.8 million of the environmental reserve ($2.9 million for CL&P, $5.9 million for PSNH and $0.3 million for WMECO), determining an estimated range of loss is not possible at this time.

CY2011

us-gaap

Site Contingency Unasserted Claims

SiteContingencyUnassertedClaims

As of December 31, 2011, in addition to the sites identified above, there were 12 sites (7 for CL&P, 2 for PSNH and 2 for WMECO) for which there are unasserted claims; however, any related site assessment or remediation costs are not probable or estimable at this time.

CY2011Q4

nu

Superfund Site Information

SuperfundSiteInformation

CERCLA: CERCLA and its amendments or state equivalents impose joint and several strict liabilities, regardless of fault, upon generators of hazardous substances resulting in removal and remediation costs and environmental damages.  Liabilities under these laws can be material and in some instances may be imposed without regard to fault or for past acts that may have been lawful at the time they occurred.  Of the total sites included in the remediation and long-term monitoring phase, 6 sites (4 for PSNH, 2 for CL&P and 1 for WMECO) are superfund sites under CERCLA for which the Company has been notified that it is a potentially responsible party but for which the site assessment and remediation are not being managed by the Company.  As of December 31, 2011, a liability of $0.7 million ($0.3 million for CL&P and $0.4 million for PSNH) accrued on these sites represents management's best estimate of its potential remediation costs with respect to these superfund sites.

CY2011

nu

Cumulative Payments Environmental Loss Contingencies

CumulativePaymentsEnvironmentalLossContingencies

17100000

USD

CY2011Q4

us-gaap

Unrecorded Unconditional Purchase Obligation Balance On Third Anniversary

UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary

567400000

USD

CY2011Q4

us-gaap

Unrecorded Unconditional Purchase Obligation Balance On Fourth Anniversary

UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary

508100000

USD

CY2011Q4

us-gaap

Unrecorded Unconditional Purchase Obligation Balance On Fifth Anniversary

UnrecordedUnconditionalPurchaseObligationBalanceOnFifthAnniversary

493000000

USD

CY2011Q4

us-gaap

Unrecorded Unconditional Purchase Obligation Due After Five Years

UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears

4129100000

USD

CY2011Q4

us-gaap

Unrecorded Unconditional Purchase Obligation Balance Sheet Amount

UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount

6847300000

USD

CY2011Q4

us-gaap

Unrecorded Unconditional Purchase Obligation Balance On First Anniversary

UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary

613500000

USD

CY2011Q4

us-gaap

Unrecorded Unconditional Purchase Obligation Balance On Second Anniversary

UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary

536200000

USD

CY2010

nu

Supply And Stranded Costs Obligations Incurred

SupplyAndStrandedCostsObligationsIncurred

196200000

USD

CY2009

nu

Supply And Stranded Costs Obligations Incurred

SupplyAndStrandedCostsObligationsIncurred

205300000

USD

CY2010

nu

Transmission Support Commitment Costs Incurred

TransmissionSupportCommitmentCostsIncurred

18900000

USD

CY2009

nu

Transmission Support Commitment Costs Incurred

TransmissionSupportCommitmentCostsIncurred

18600000

USD

CY2010

nu

Yankee Companies Billings Incurred

YankeeCompaniesBillingsIncurred

33000000

USD

CY2009

nu

Yankee Companies Billings Incurred

YankeeCompaniesBillingsIncurred

26900000

USD

CY2011

nu

Supply And Stranded Costs Obligations Incurred

SupplyAndStrandedCostsObligationsIncurred

132200000

USD

CY2011

nu

Transmission Support Commitment Costs Incurred

TransmissionSupportCommitmentCostsIncurred

18100000

USD

CY2011

nu

Yankee Companies Billings Incurred

YankeeCompaniesBillingsIncurred

26600000

USD

CY2011Q4

nu

Capacity Cfd Expense Incurred

CapacityCfdExpenseIncurred

23800000

USD

CY2011Q4

nu

Peaker Cfd Expense Incurred

PeakerCfdExpenseIncurred

40200000

USD

CY2010Q4

nu

Peaker Cfd Expense Incurred

PeakerCfdExpenseIncurred

10000000

USD

CY2011Q4

nu

Court Of Federal Claims Ruling To Cyapc

CourtOfFederalClaimsRulingToCyapc

34200000

USD

CY2011Q4

nu

Court Of Federal Claims Ruling To Yaec

CourtOfFederalClaimsRulingToYaec

32900000

USD

CY2011Q4

nu

Court Of Federal Claims Ruling To Myapc

CourtOfFederalClaimsRulingToMyapc

75800000

USD

CY2011Q4

nu

Trial Court Ruling To Cyapc

TrialCourtRulingToCyapc

39700000

USD

CY2011Q4

nu

Trial Court Ruling To Yaec

TrialCourtRulingToYaec

21200000

USD

CY2011Q4

nu

Trial Court Ruling To Myapc

TrialCourtRulingToMyapc

81700000

USD

CY2011

nu

Payments Made On Capital Leases Total

PaymentsMadeOnCapitalLeasesTotal

2700000

USD

CY2010

nu

Payments Made On Capital Leases Total

PaymentsMadeOnCapitalLeasesTotal

2500000

USD

CY2009

nu

Payments Made On Capital Leases Total

PaymentsMadeOnCapitalLeasesTotal

2600000

USD

CY2011

us-gaap

Capital Leases Income Statement Interest Expense

CapitalLeasesIncomeStatementInterestExpense

1700000

USD

CY2010

us-gaap

Capital Leases Income Statement Interest Expense

CapitalLeasesIncomeStatementInterestExpense

1800000

USD

CY2009

us-gaap

Capital Leases Income Statement Interest Expense

CapitalLeasesIncomeStatementInterestExpense

1900000

USD

CY2009

us-gaap

Capital Leases Income Statement Amortization Expense

CapitalLeasesIncomeStatementAmortizationExpense

600000

USD

CY2010

us-gaap

Capital Leases Income Statement Amortization Expense

CapitalLeasesIncomeStatementAmortizationExpense

700000

USD

CY2011

us-gaap

Capital Leases Income Statement Amortization Expense

CapitalLeasesIncomeStatementAmortizationExpense

1000000

USD

CY2011

us-gaap

Lease And Rental Expense

LeaseAndRentalExpense

8400000

USD

CY2010

us-gaap

Lease And Rental Expense

LeaseAndRentalExpense

11900000

USD

CY2009

us-gaap

Lease And Rental Expense

LeaseAndRentalExpense

18100000

USD

CY2011Q4

nu

Capitalized Portion Of Operating Lease

CapitalizedPortionOfOperatingLease

1400000

USD

CY2010Q4

nu

Capitalized Portion Of Operating Lease

CapitalizedPortionOfOperatingLease

4800000

USD

CY2009Q4

nu

Capitalized Portion Of Operating Lease

CapitalizedPortionOfOperatingLease

9700000

USD

CY2011Q4

us-gaap

Capital Leases Future Minimum Payments Due In Two Years

CapitalLeasesFutureMinimumPaymentsDueInTwoYears

2600000

USD

CY2011Q4

us-gaap

Capital Leases Future Minimum Payments Due In Three Years

CapitalLeasesFutureMinimumPaymentsDueInThreeYears

2200000

USD

CY2011Q4

us-gaap

Capital Leases Future Minimum Payments Due In Four Years

CapitalLeasesFutureMinimumPaymentsDueInFourYears

2200000

USD

CY2011Q4

us-gaap

Capital Leases Future Minimum Payments Due In Five Years

CapitalLeasesFutureMinimumPaymentsDueInFiveYears

2000000

USD

CY2011Q4

us-gaap

Capital Leases Future Minimum Payments Due Thereafter

CapitalLeasesFutureMinimumPaymentsDueThereafter

9500000

USD

CY2011Q4

us-gaap

Capital Leases Future Minimum Payments Due

CapitalLeasesFutureMinimumPaymentsDue

21500000

USD

CY2011Q4

us-gaap

Capital Leases Future Minimum Payments Interest Included In Payments

CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments

9100000

USD

CY2011Q4

us-gaap

Capital Leases Future Minimum Payments Present Value Of Net Minimum Payments

CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments

12400000

USD

CY2011Q4

us-gaap

Operating Leases Future Minimum Payments Due Current

OperatingLeasesFutureMinimumPaymentsDueCurrent

7700000

USD

CY2011Q4

us-gaap

Operating Leases Future Minimum Payments Due In Two Years

OperatingLeasesFutureMinimumPaymentsDueInTwoYears

6900000

USD

CY2011Q4

us-gaap

Operating Leases Future Minimum Payments Due In Three Years

OperatingLeasesFutureMinimumPaymentsDueInThreeYears

4900000

USD

CY2011Q4

us-gaap

Operating Leases Future Minimum Payments Due In Four Years

OperatingLeasesFutureMinimumPaymentsDueInFourYears

4300000

USD

CY2011Q4

us-gaap

Operating Leases Future Minimum Payments Due In Five Years

OperatingLeasesFutureMinimumPaymentsDueInFiveYears

4300000

USD

CY2011Q4

us-gaap

Operating Leases Future Minimum Payments Due Thereafter

OperatingLeasesFutureMinimumPaymentsDueThereafter

16600000

USD

CY2011Q4

us-gaap

Operating Leases Future Minimum Payments Due

OperatingLeasesFutureMinimumPaymentsDue

44700000

USD

CY2011

nu

Preferred Stock Text Block1

PreferredStockTextBlock1

15.       PREFERRED STOCK NOT SUBJECT TO MANDATORY REDEMPTION (CL&P) CL&P's charter authorizes it to issue up to 9 million shares of preferred stock ($50 par value per share) of which 2,324,000 shares were outstanding as of December 31, 2011 and 2010. CL&P amended its charter on January 3, 2012 to remove references to various series of preferred stock, including the Class A preferred stock, which are no longer outstanding. There were no Class A preferred shares outstanding as of December 31, 2011 and 2010. The issuance of additional preferred shares would be subject to approval by the PURA.  Preferred stockholders have liquidation rights equal to the par value of the preferred stock, which they would receive in preference to any distributions to any junior stock. Were there to be a shortfall, all preferred stockholders would share ratably in available liquidation assets. Details of preferred stock not subject to mandatory redemption are as follows (in millions except in redemption price and shares):<div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 32px; text-align:left;border-color:#000000;min-width:32px;"> </td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; text-align:center;border-color:#000000;min-width:100px;">December 31, 2011</td><td rowspan="2" style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:center;border-color:#000000;min-width:145px;">Shares Outstanding as of</td><td rowspan="2" style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td colspan="5" style="width: 210px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:210px;">As of December 31,</td></tr><tr style="height: 10px"><td colspan="4" style="width: 250px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:250px;">Description</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;">Redemption Price</td><td style="width: 145px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:145px;">December 31, 2011 and 2010</td><td colspan="2" style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;">2011</td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td colspan="2" style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;">2010</td></tr><tr style="height: 10px"><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 32px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:32px;"> 1.90</td><td style="width: 15px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 193px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:193px;">Series of 1947</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:90px;">52.50</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:145px;">163,912</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:90px;"> 8.2</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:90px;"> 8.2</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 2.00</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series of 1947</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">54.00</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">336,088</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 16.8</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 16.8</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 2.04</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series of 1949</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">52.00</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">100,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 5.0</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 5.0</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 2.20</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series of 1949</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">52.50</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">200,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 10.0</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 10.0</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 3.90</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;">%</td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series of 1949</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">50.50</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">160,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 8.0</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 8.0</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 2.06</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series E of 1954</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">51.00</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">200,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 10.0</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 10.0</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 2.09</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series F of 1955</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">51.00</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">100,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 5.0</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 5.0</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 4.50</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;">%</td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series of 1956</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">50.75</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">104,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 5.2</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 5.2</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 4.96</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;">%</td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series of 1958</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">50.50</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">100,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 5.0</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 5.0</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 4.50</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;">%</td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series of 1963</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">50.50</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">160,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 8.0</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 8.0</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 5.28</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;">%</td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series of 1967</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">51.43</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">200,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 10.0</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 10.0</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 3.24</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series G of 1968</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">51.84</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; text-align:right;border-color:#000000;min-width:145px;">300,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 15.0</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;"> 15.0</td></tr><tr style="height: 10px"><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 32px; text-align:center;border-color:#000000;min-width:32px;"> 6.56</td><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;">%</td><td style="width: 193px; text-align:left;border-color:#000000;min-width:193px;">Series of 1968</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; text-align:right;border-color:#000000;min-width:90px;">51.44</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:145px;">200,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> 10.0</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> 10.0</td></tr><tr style="height: 10px"><td colspan="4" style="width: 250px; text-align:left;border-color:#000000;min-width:250px;">Totals</td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 90px; text-align:left;border-color:#000000;min-width:90px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 145px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:145px;">2,324,000</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> 116.2</td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;">$</td><td style="width: 90px; border-top-style:solid;border-top-width:1px;border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:90px;"> 116.2</td></tr></table></div>Dividends totaling $5.6 million for 2011, $6.1 million for 2010 and $5.6 million for 2009 were declared and dividends of $5.6 million were paid to the preferred stockholders in 2011, 2010 and 2009.

CY2010Q4

us-gaap

Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax

AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax

600000

USD

CY2010Q4

us-gaap

Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax

AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax

39800000

USD

CY2011Q4

us-gaap

Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax

AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax

1100000

USD

CY2011Q4

us-gaap

Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax

AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax

53400000

USD

CY2011

us-gaap

Other Comprehensive Income Reclassification Adjustment On Derivatives Included In Net Income Net Of Tax

OtherComprehensiveIncomeReclassificationAdjustmentOnDerivativesIncludedInNetIncomeNetOfTax

-700000

USD

CY2011

us-gaap

Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax

OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax

-14900000

USD

CY2011Q4

us-gaap

Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax

AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax

-18400000

USD

CY2010Q4

us-gaap

Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax

AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax

-4200000

USD

CY2011

us-gaap

Other Comprehensive Income Derivatives Qualifying As Hedges Tax Effect Period Increase Decrease

OtherComprehensiveIncomeDerivativesQualifyingAsHedgesTaxEffectPeriodIncreaseDecrease

9500000

USD

CY2010

us-gaap

Other Comprehensive Income Derivatives Qualifying As Hedges Tax Effect Period Increase Decrease

OtherComprehensiveIncomeDerivativesQualifyingAsHedgesTaxEffectPeriodIncreaseDecrease

-200000

USD

CY2009

us-gaap

Other Comprehensive Income Derivatives Qualifying As Hedges Tax Effect Period Increase Decrease

OtherComprehensiveIncomeDerivativesQualifyingAsHedgesTaxEffectPeriodIncreaseDecrease

-200000

USD

CY2009

us-gaap

Other Comprehensive Income Available For Sale Securities Tax

OtherComprehensiveIncomeAvailableForSaleSecuritiesTax

700000

USD

CY2010

us-gaap

Other Comprehensive Income Available For Sale Securities Tax

OtherComprehensiveIncomeAvailableForSaleSecuritiesTax

-200000

USD

CY2011

us-gaap

Other Comprehensive Income Available For Sale Securities Tax

OtherComprehensiveIncomeAvailableForSaleSecuritiesTax

-400000

USD

CY2011

us-gaap

Other Comprehensive Income Defined Benefit Plans Tax

OtherComprehensiveIncomeDefinedBenefitPlansTax

7900000

USD

CY2010

us-gaap

Other Comprehensive Income Defined Benefit Plans Tax

OtherComprehensiveIncomeDefinedBenefitPlansTax

0

USD

CY2009

us-gaap

Other Comprehensive Income Defined Benefit Plans Tax

OtherComprehensiveIncomeDefinedBenefitPlansTax

2900000

USD

CY2011

us-gaap

Other Comprehensive Income Loss Tax Portion Attributable To Parent

OtherComprehensiveIncomeLossTaxPortionAttributableToParent

17000000

USD

CY2010

us-gaap

Other Comprehensive Income Loss Tax Portion Attributable To Parent

OtherComprehensiveIncomeLossTaxPortionAttributableToParent

-400000

USD

CY2009

us-gaap

Other Comprehensive Income Loss Tax Portion Attributable To Parent

OtherComprehensiveIncomeLossTaxPortionAttributableToParent

3400000

USD

CY2011

us-gaap

Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months

CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths

-2200000

USD

CY2011

nu

Pension Serp And Pbop Gain Loss To Be Reclassified Within Twelve Months

PensionSerpAndPbopGainLossToBeReclassifiedWithinTwelveMonths

-8700000

USD

CY2011

us-gaap

Line Of Credit Facility Dividend Restrictions

LineOfCreditFacilityDividendRestrictions

CL&P, PSNH and WMECO are subject to Section 305 of the Federal Power Act that makes it unlawful for a public utility to make or pay a dividend from any funds "properly included in its capital account." Management believes that this Federal Power Act restriction, as applied to CL&P, PSNH and WMECO, would not be construed or applied by the FERC to prohibit the payment of dividends for lawful and legitimate business purposes from retained earnings. In addition, certain state statutes may impose additional limitations on such companies and on Yankee Gas. Such state law restrictions do not restrict payment of dividends from retained earnings or net income. CL&P, PSNH, WMECO and Yankee Gas also have a revolving credit agreement that imposes leverage restrictions including consolidated total debt to total capitalization ratio requirements. The Retained Earnings balances subject to these leverage restrictions are $1.652 billion for NU, $735.9 million for CL&P, $388.9 million for PSNH and $115.5 million for WMECO as of December 31, 2011.

CY2011Q4

us-gaap

Common Stock Par Or Stated Value Per Share

CommonStockParOrStatedValuePerShare

5

CY2010Q4

us-gaap

Common Stock Shares Issued

CommonStockSharesIssued

195781740

shares

CY2011Q4

us-gaap

Common Stock Shares Issued

CommonStockSharesIssued

196052770

shares

CY2010Q4

us-gaap

Common Stock Shares Authorized

CommonStockSharesAuthorized

225000000

shares

CY2011Q4

us-gaap

Common Stock Shares Authorized

CommonStockSharesAuthorized

380000000

shares

CY2011Q4

us-gaap

Treasury Stock Shares

TreasuryStockShares

18894078

shares

CY2010Q4

us-gaap

Treasury Stock Shares

TreasuryStockShares

19333659

shares

CY2010

us-gaap

Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount

AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

1578

shares

CY2011

us-gaap

Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount

AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

4314

shares

CY2009

us-gaap

Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount

AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

17637

shares

CY2011

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Weighted Average Number Diluted Shares Outstanding Adjustment

WeightedAverageNumberDilutedSharesOutstandingAdjustment

394401

shares

CY2010

us-gaap

Weighted Average Number Diluted Shares Outstanding Adjustment

WeightedAverageNumberDilutedSharesOutstandingAdjustment

249301

shares

CY2009

us-gaap

Weighted Average Number Diluted Shares Outstanding Adjustment

WeightedAverageNumberDilutedSharesOutstandingAdjustment

149318

shares

CY2011

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

2.22

CY2010

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

2.20

CY2009

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

1.91

CY2011

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

2.22

CY2010

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

2.19

CY2009

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

1.91

CY2011

us-gaap

Depreciation Depletion And Amortization

DepreciationDepletionAndAmortization

469200000

USD

CY2011

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Utilities Operating Expense Other

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3202300000

USD

CY2010

us-gaap

Depreciation Depletion And Amortization

DepreciationDepletionAndAmortization

629200000

USD

CY2010

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Utilities Operating Expense Other

UtilitiesOperatingExpenseOther

3469100000

USD

CY2009

us-gaap

Depreciation Depletion And Amortization

DepreciationDepletionAndAmortization

540800000

USD

CY2009

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Utilities Operating Expense Other

UtilitiesOperatingExpenseOther

4147200000

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CY2011

us-gaap

Valuation Allowances And Reserves Charged To Cost And Expense

ValuationAllowancesAndReservesChargedToCostAndExpense

16420000

USD

CY2011

dei

Document Period End Date

DocumentPeriodEndDate

2011-12-31

CY2011Q2

us-gaap

Revenues

1047500000

USD

CY2011Q3

us-gaap

Revenues

1114900000

USD

CY2011Q3

us-gaap

Operating Income Loss

OperatingIncomeLoss

203800000

USD

CY2011Q2

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Operating Income Loss

OperatingIncomeLoss

178100000

USD

CY2011Q2

us-gaap

Net Income Loss

NetIncomeLoss

78700000

USD

CY2011Q3

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Net Income Loss

NetIncomeLoss

91400000

USD

CY2011Q3

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

90000000

USD

CY2011Q2

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

77300000

USD

CY2010Q2

us-gaap

Revenues

1111400000

USD

CY2010Q3

us-gaap

Revenues

1243300000

USD

CY2010Q3

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Operating Income Loss

OperatingIncomeLoss

199600000

USD

CY2010Q2

us-gaap

Operating Income Loss

OperatingIncomeLoss

178300000

USD

CY2010Q2

us-gaap

Net Income Loss

NetIncomeLoss

73300000

USD

CY2010Q3

us-gaap

Net Income Loss

NetIncomeLoss

101900000

USD

CY2010Q3

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

100500000

USD

CY2010Q2

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

71900000

USD

CY2011Q1

us-gaap

Revenues

1235300000

USD

CY2011Q1

us-gaap

Operating Income Loss

OperatingIncomeLoss

227400000

USD

CY2011Q1

us-gaap

Net Income Loss

NetIncomeLoss

115600000

USD

CY2010Q1

us-gaap

Revenues

1339400000

USD

CY2010Q1

us-gaap

Operating Income Loss

OperatingIncomeLoss

226700000

USD

CY2010Q1

us-gaap

Net Income Loss

NetIncomeLoss

87600000

USD

CY2010Q1

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

86200000

USD

CY2011Q1

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

114200000

USD

CY2011Q4

us-gaap

Revenues

1068000000

USD

CY2011Q4

us-gaap

Operating Income Loss

OperatingIncomeLoss

184900000

USD

CY2011Q4

us-gaap

Net Income Loss

NetIncomeLoss

114800000

USD

CY2011Q4

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

113200000

USD

CY2010Q4

us-gaap

Revenues

1204100000

USD

CY2011

dei

Entity Central Index Key

EntityCentralIndexKey

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CY2010Q3

us-gaap

Earnings Per Share Basic And Diluted

EarningsPerShareBasicAndDiluted

0.57

CY2010Q4

us-gaap

Operating Income Loss

OperatingIncomeLoss

195300000

USD

CY2011

dei

Current Fiscal Year End Date

CurrentFiscalYearEndDate

--12-31

CY2010Q2

us-gaap

Earnings Per Share Basic And Diluted

EarningsPerShareBasicAndDiluted

0.41

CY2010Q1

us-gaap

Earnings Per Share Basic And Diluted

EarningsPerShareBasicAndDiluted

0.49

CY2010Q4

us-gaap

Net Income Loss

NetIncomeLoss

131300000

USD

CY2010Q4

us-gaap

Net Income Loss Available To Common Stockholders Basic

NetIncomeLossAvailableToCommonStockholdersBasic

129300000

USD

CY2011Q1

us-gaap

Earnings Per Share Basic And Diluted

EarningsPerShareBasicAndDiluted

0.64

CY2011Q2

us-gaap

Earnings Per Share Basic And Diluted

EarningsPerShareBasicAndDiluted

0.44

CY2011Q3

us-gaap

Earnings Per Share Basic And Diluted

EarningsPerShareBasicAndDiluted

0.51

CY2011Q4

us-gaap

Earnings Per Share Basic And Diluted

EarningsPerShareBasicAndDiluted

0.64

CY2010Q4

us-gaap

Earnings Per Share Basic And Diluted

EarningsPerShareBasicAndDiluted

0.73

CY2010

us-gaap

Valuation Allowances And Reserves Charged To Cost And Expense

ValuationAllowancesAndReservesChargedToCostAndExpense

31352000

USD

CY2009

us-gaap

Valuation Allowances And Reserves Charged To Cost And Expense

ValuationAllowancesAndReservesChargedToCostAndExpense

53947000

USD

CY2011

us-gaap

Valuation Allowances And Reserves Charged To Other Accounts

ValuationAllowancesAndReservesChargedToOtherAccounts

8664000

USD

CY2010

us-gaap

Valuation Allowances And Reserves Charged To Other Accounts

ValuationAllowancesAndReservesChargedToOtherAccounts

10714000

USD

CY2009

us-gaap

Valuation Allowances And Reserves Charged To Other Accounts

ValuationAllowancesAndReservesChargedToOtherAccounts

24136000

USD

CY2011

us-gaap

Valuation Allowances And Reserves Deductions

ValuationAllowancesAndReservesDeductions

30020000

USD

CY2010

us-gaap

Valuation Allowances And Reserves Deductions

ValuationAllowancesAndReservesDeductions

57569000

USD

CY2009

us-gaap

Valuation Allowances And Reserves Deductions

ValuationAllowancesAndReservesDeductions

66058000

USD

CY2008Q4

us-gaap

Valuation Allowances And Reserves Balance

ValuationAllowancesAndReservesBalance

43275000

USD

CY2009Q4

us-gaap

Valuation Allowances And Reserves Balance

ValuationAllowancesAndReservesBalance

55300000

USD

CY2010Q4

us-gaap

Valuation Allowances And Reserves Balance

ValuationAllowancesAndReservesBalance

39797000

USD

CY2011Q4

us-gaap

Valuation Allowances And Reserves Balance

ValuationAllowancesAndReservesBalance

34861000

USD

CY2011

dei

Entity Registrant Name

EntityRegistrantName

NORTHEAST UTILITIES

CY2011

dei

Document Type

DocumentType

10-K

CY2012Q1

dei

Entity Common Stock Shares Outstanding

EntityCommonStockSharesOutstanding

177203768

shares

CY2011Q2

dei

Entity Public Float

EntityPublicFloat

6218948650

USD

CY2011

dei

Entity Filer Category

EntityFilerCategory

Large Accelerated Filer

CY2011

dei

Entity Current Reporting Status

EntityCurrentReportingStatus

Yes

CY2011

dei

Entity Voluntary Filers

EntityVoluntaryFilers

No

CY2011

dei

Entity Well Known Seasoned Issuer

EntityWellKnownSeasonedIssuer

Yes

CY2011

dei

Document Fiscal Year Focus

DocumentFiscalYearFocus

2011

CY2011

dei

Document Fiscal Period Focus

DocumentFiscalPeriodFocus

FY

CY2011

dei

Amendment Flag

AmendmentFlag

false

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$ES
EVERSOURCE ENERGY Stock $es

2011 Q4 Form 10-K Financial Statement

#000007274112000020 Filed on February 24, 2012

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ES EVERSOURCE ENERGY Stock $es

2011 Q4 Form 10-K Financial Statement

#000007274112000020 Filed on February 24, 2012

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ES
EVERSOURCE ENERGY Stock $es