$ES
EVERSOURCE ENERGY Stock $es

$es Overview Financials Valuation SEC Filings Company Website

2014 Q4 Form 10-K Financial Statement

#000007274115000013 Filed on February 25, 2015

Income Statement

Concept	2014 Q4	2013 Q4	2013 Q3
Revenue	$1.881B	$1.778B	$1.893B
YoY Change	5.82%	5.56%	1.67%
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	$158.5M	$147.2M	$149.1M
YoY Change	7.68%	-1.34%	-35.54%
% of Gross Profit
Operating Expenses	$1.451B	$1.417B	$1.493B
YoY Change	2.39%	4.77%	3.09%
Operating Profit	$430.2M	$360.6M	$399.3M
YoY Change	19.3%	8.81%	-3.29%
Interest Expense	-$89.90M	-$88.10M	$87.48M
YoY Change	2.04%	4.76%	-3.19%
% of Operating Profit	-20.9%	-24.43%	21.91%
Other Income/Expense, Net	$5.600M	$8.200M	$8.945M
YoY Change	-31.71%	70.83%	106.87%
Pretax Income	$345.9M	$280.8M	$320.7M
YoY Change	23.18%	11.38%	-1.89%
Income Tax	$122.4M	$101.5M	$109.4M
% Of Pretax Income	35.39%	36.15%	34.11%
Net Earnings	$223.6M	$179.2M	$211.4M
YoY Change	24.78%	1.47%	0.91%
Net Earnings / Revenue	11.89%	10.08%	11.17%
Basic Earnings Per Share			$0.66
Diluted Earnings Per Share	$696.6K	$560.2K	$0.66
COMMON SHARES
Basic Shares Outstanding	316.8M shares	315.1M shares	315.3M shares
Diluted Shares Outstanding			316.2M shares

Balance Sheet

Concept	2014 Q4	2013 Q4	2013 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$39.00M	$43.00M	$58.00M
YoY Change	-9.3%	-6.52%	-62.58%
Cash & Equivalents	$39.00M	$43.00M	$58.00M
Short-Term Investments
Other Short-Term Assets	$1.110B	$214.3M	$871.0M
YoY Change	417.99%	7.17%	671.04%
Inventory	$350.0M	$303.0M	$305.0M
Prepaid Expenses
Receivables	$856.0M	$765.0M	$784.0M
Other Receivables	$338.0M	$17.00M	$0.00
Total Short-Term Assets	$2.692B	$2.087B	$2.018B
YoY Change	28.99%	-6.3%	-5.66%
LONG-TERM ASSETS
Property, Plant & Equipment	$18.65B	$17.58B	$17.19B
YoY Change	6.09%	5.85%	5.42%
Goodwill	$3.519B	$3.519B
YoY Change	0.0%	0.0%
Intangibles
YoY Change
Long-Term Investments	$515.0M	$489.0M	$468.0M
YoY Change	5.32%	22.25%	18.78%
Other Assets	$312.4M	$291.5M	$5.251B
YoY Change	7.15%	-11.05%	1645.56%
Total Long-Term Assets	$8.401B	$8.132B	$26.43B
YoY Change	3.3%	-14.13%	183.7%
TOTAL ASSETS
Total Short-Term Assets	$2.692B	$2.087B	$2.018B
Total Long-Term Assets	$8.401B	$8.132B	$26.43B
Total Assets	$29.74B	$27.80B	$28.44B
YoY Change	7.0%	-1.79%	2.47%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$868.2M	$742.3M	$554.0M
YoY Change	16.97%	-2.89%	2.08%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$957.0M	$1.093B	$1.343B
YoY Change	-12.44%	-2.41%	-1.18%
Long-Term Debt Due	$245.6M	$533.3M	$608.0M
YoY Change	-53.95%	-30.13%	-30.89%
Total Short-Term Liabilities	$3.134B	$3.276B	$3.378B
YoY Change	-4.31%	-10.1%	-11.12%
LONG-TERM LIABILITIES
Long-Term Debt	$8.606B	$7.777B	$7.444B
YoY Change	10.66%	8.01%	10.57%
Other Long-Term Liabilities	$874.4M	$923.1M	$3.994B
YoY Change	-5.27%	-4.6%	358.33%
Total Long-Term Liabilities	$7.905B	$6.976B	$11.44B
YoY Change	13.32%	-12.63%	46.82%
TOTAL LIABILITIES
Total Short-Term Liabilities	$3.134B	$3.276B	$3.378B
Total Long-Term Liabilities	$7.905B	$6.976B	$11.44B
Total Liabilities	$11.04B	$10.25B	$18.77B
YoY Change	7.69%	-11.84%	61.94%
SHAREHOLDERS EQUITY
Retained Earnings	$2.449B	$2.126B
YoY Change	15.18%	17.93%
Common Stock	$1.667B	$1.665B
YoY Change	0.09%	0.17%
Preferred Stock
YoY Change
Treasury Stock (at cost)	-$300.5M	-$326.5M
YoY Change	-7.98%	-3.57%
Treasury Stock Shares	16.38M shares	17.80M shares	18.14M shares
Shareholders Equity	$9.977B	$9.612B	$9.673B
YoY Change
Total Liabilities & Shareholders Equity	$29.78B	$27.80B	$28.44B
YoY Change	7.13%	-1.79%	2.47%

Cashflow Statement

Concept	2014 Q4	2013 Q4	2013 Q3
OPERATING ACTIVITIES
Net Income	$223.6M	$179.2M	$211.4M
YoY Change	24.78%	1.47%	0.91%
Depreciation, Depletion And Amortization	$158.5M	$147.2M	$149.1M
YoY Change	7.68%	-1.34%	-35.54%
Cash From Operating Activities	$248.0M	$486.5M	$408.0M
YoY Change	-49.02%	33.21%	-14.21%
INVESTING ACTIVITIES
Capital Expenditures	-$486.2M	-$383.0M	-$373.5M
YoY Change	26.95%	-1.92%	-4.57%
Acquisitions
YoY Change
Other Investing Activities	$17.60M	$800.0K	$32.40M
YoY Change	2100.0%	-104.97%	63.64%
Cash From Investing Activities	-$468.6M	-$382.2M	-$341.2M
YoY Change	22.61%	-6.0%	-8.18%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	217.7M	-118.9M	-44.90M
YoY Change	-283.1%	-967.88%	-24.03%
NET CHANGE
Cash From Operating Activities	248.0M	486.5M	408.0M
Cash From Investing Activities	-468.6M	-382.2M	-341.2M
Cash From Financing Activities	217.7M	-118.9M	-44.90M
Net Change In Cash	-2.900M	-14.60M	21.90M
YoY Change	-80.14%	-47.29%	-51.22%
FREE CASH FLOW
Cash From Operating Activities	$248.0M	$486.5M	$408.0M
Capital Expenditures	-$486.2M	-$383.0M	-$373.5M
Free Cash Flow	$734.2M	$869.5M	$781.5M
YoY Change	-15.56%	15.06%	-9.86%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2013	us-gaap	Operating Expenses OperatingExpenses	5771769000	USD
CY2014	us-gaap	Operating Expenses OperatingExpenses	6109007000	USD
CY2013Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	533346000	USD
CY2012	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	1583070000	USD
CY2013	us-gaap	Interest Expense InterestExpense	338699000	USD
CY2013	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	206322000	USD
CY2014	us-gaap	Revenues Revenues	7741856000	USD
CY2014Q4	us-gaap	Stockholders Equity StockholdersEquity	9976815000	USD
CY2014Q4	us-gaap	Capitalization Longterm Debt And Equity CapitalizationLongtermDebtAndEquity	18738400000	USD
CY2014	us-gaap	Cost Of Purchased Power CostOfPurchasedPower	3021550000	USD
CY2013	us-gaap	Net Income Loss NetIncomeLoss	793689000	USD
CY2013Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	742251000	USD
CY2013	us-gaap	Depreciation Depreciation	610777000	USD
CY2013	us-gaap	Interest Expense Other InterestExpenseOther	-2693000	USD
CY2014	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	1295362000	USD
CY2013Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	702776000	USD
CY2013Q4	us-gaap	Liabilities Current LiabilitiesCurrent	3275651000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	4029026000	USD
CY2013Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	502984000	USD
CY2013Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	624050000	USD
CY2013Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	896844000	USD
CY2013Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	923053000	USD
CY2013Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	6975957000	USD
CY2013Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	7776833000	USD
CY2013Q4	us-gaap	Redeemable Noncontrolling Interest Equity Preferred Carrying Amount RedeemableNoncontrollingInterestEquityPreferredCarryingAmount	155568000	USD
CY2013Q4	us-gaap	Common Stock Value CommonStockValue	1665351000	USD
CY2013Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	6192765000	USD
CY2013Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	2125980000	USD
CY2013Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-46031000	USD
CY2013Q4	us-gaap	Treasury Stock Value TreasuryStockValue	-326537000	USD
CY2013Q4	us-gaap	Stockholders Equity StockholdersEquity	9611528000	USD
CY2013Q4	us-gaap	Capitalization Longterm Debt And Equity CapitalizationLongtermDebtAndEquity	17543929000	USD
CY2013Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	27795537000	USD
CY2013Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	204278000	USD
CY2014Q4	us-gaap	Notes Payable NotesPayable	956825000	USD
CY2014Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	245583000	USD
CY2014Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	868231000	USD
CY2014Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	235022000	USD
CY2014Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	828720000	USD
CY2014Q4	us-gaap	Liabilities Current LiabilitiesCurrent	3134381000	USD
CY2014Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	4467473000	USD
CY2014Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	515144000	USD
CY2014Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	409632000	USD
CY2014Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	1638558000	USD
CY2014Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	874387000	USD
CY2014Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	7905194000	USD
CY2014Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	8606017000	USD
CY2014Q4	us-gaap	Redeemable Noncontrolling Interest Equity Preferred Carrying Amount RedeemableNoncontrollingInterestEquityPreferredCarryingAmount	155568000	USD
CY2014Q4	us-gaap	Common Stock Value CommonStockValue	1666796000	USD
CY2014Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	6235834000	USD
CY2014Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	2448661000	USD
CY2014	us-gaap	Depreciation Depreciation	614657000	USD
CY2014	us-gaap	Amortization Of Regulatory Asset AmortizationOfRegulatoryAsset	10704000	USD
CY2014	us-gaap	Interest Expense Other InterestExpenseOther	17105000	USD
CY2014	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	0	USD
CY2013	us-gaap	Cost Of Purchased Power CostOfPurchasedPower	2482954000	USD
CY2013	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	512230000	USD
CY2013	us-gaap	Revenues Revenues	7301204000	USD
CY2013	us-gaap	Operating Income Loss OperatingIncomeLoss	1529435000	USD
CY2013	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	42581000	USD
CY2012	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	525945000	USD
CY2014	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	561380000	USD
CY2014	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	345001000	USD
CY2013	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	340970000	USD
CY2014	us-gaap	Interest Expense Other Long Term Debt InterestExpenseOtherLongTermDebt	0	USD
CY2013	us-gaap	Interest Expense Other Long Term Debt InterestExpenseOtherLongTermDebt	422000	USD
CY2013	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	1220630000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	808003000	USD
CY2014	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	468297000	USD
CY2013	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	426941000	USD
CY2014	us-gaap	Operating Income Loss OperatingIncomeLoss	1632849000	USD
CY2012	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	274926000	USD
CY2014	us-gaap	Net Income Loss NetIncomeLoss	827065000	USD
CY2012	us-gaap	Net Income Loss NetIncomeLoss	533077000	USD
CY2014	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	7519000	USD
CY2013	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	7682000	USD
CY2012	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	7132000	USD
CY2014	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	819546000	USD
CY2013	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	786007000	USD
CY2014	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	1427589000	USD
CY2013	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	1514986000	USD
CY2012	nu	Energy Efficiency Programs EnergyEfficiencyPrograms	313149000	USD
CY2014	nu	Energy Efficiency Programs EnergyEfficiencyPrograms	473127000	USD
CY2013	nu	Energy Efficiency Programs EnergyEfficiencyPrograms	401919000	USD
CY2014	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	24619000	USD
CY2013	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	29894000	USD
CY2012	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	19742000	USD
CY2014	us-gaap	Interest Expense InterestExpense	362106000	USD
CY2012	us-gaap	Interest Expense InterestExpense	329945000	USD
CY2014	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	2037000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	2049000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	217000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	25714000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-2168000	USD
CY2013	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-7682000	USD
CY2012	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	523777000	USD
CY2013	nu	Sharesissuedvalueinconectionwithnstarmerger Sharesissuedvalueinconectionwithnstarmerger		USD
CY2013	nu	Sharesissuedinconnectionwithnstarmerger Sharesissuedinconnectionwithnstarmerger		shares
CY2014	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	443259000	USD
CY2014	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	99056000	USD
CY2014	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	-6853000	USD
CY2014	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	39523000	USD
CY2014	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	122139000	USD
CY2014	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	41310000	USD
CY2014	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	323224000	USD
CY2014	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	144743000	USD
CY2014	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-15797000	USD
CY2014	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1635473000	USD
CY2014	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1603744000	USD
CY2014	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	488789000	USD
CY2014	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	491220000	USD
CY2014	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-14380000	USD
CY2014	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1591795000	USD
CY2014	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	0	USD
CY2014	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	883000	USD
CY2014	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-48339000	USD
CY2014	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-4661000	USD
CY2014	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	576551000	USD
CY2012	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	292000000	USD
CY2012	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	218540000	USD
CY2012	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	259853000	USD
CY2012	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	42852000	USD
CY2012	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	20214000	USD
CY2012	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-34321000	USD
CY2012	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	5450000	USD
CY2012	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-128339000	USD
CY2012	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-8532000	USD
CY2012	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1161229000	USD
CY2012	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1472272000	USD
CY2012	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	317294000	USD
CY2012	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	348629000	USD
CY2012	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-35683000	USD
CY2012	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1467924000	USD
CY2012	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	114433000	USD
CY2012	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	839136000	USD
CY2012	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	6529000	USD
CY2012	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	345884000	USD
CY2012	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	39189000	USD
CY2011Q4	us-gaap	Cash Cash	6559000	USD
CY2014	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	475227000	USD
CY2014	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	7519000	USD
CY2014	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	285075000	USD
CY2014	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	725000000	USD
CY2012	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	375047000	USD
CY2012	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	7029000	USD
CY2012	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	825000000	USD
CY2012	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	850000000	USD
CY2014	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	211649000	USD
CY2012	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	295028000	USD
CY2013	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	431413000	USD
CY2013	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	195698000	USD
CY2013	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	342184000	USD
CY2013	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	24276000	USD
CY2013	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	56071000	USD
CY2013	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	163549000	USD
CY2013	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	14811000	USD
CY2013	us-gaap	Increase Decrease In Income Taxes Receivable IncreaseDecreaseInIncomeTaxesReceivable	50950000	USD
CY2013	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-54619000	USD
CY2013	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	22623000	USD
CY2013	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1663539000	USD
CY2013	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1456787000	USD
CY2013	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	627532000	USD
CY2013	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	679784000	USD
CY2013	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-67816000	USD
CY2013	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1441223000	USD
CY2013	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	462741000	USD
CY2013	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	7682000	USD
CY2013	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-397000000	USD
CY2013	us-gaap	Fuel Costs FuelCosts	139500000	USD
CY2014	us-gaap	Fuel Costs FuelCosts	164300000	USD
CY2013	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1680000000	USD
CY2013	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	82139000	USD
CY2013	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-25253000	USD
CY2013	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-224700000	USD
CY2013	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-2384000	USD
CY2012Q4	us-gaap	Cash Cash	45748000	USD
CY2014	nu	Proceeds From Doe Damages Claim Net ProceedsFromDoeDamagesClaimNet	132138000	USD
CY2013Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	171300000	USD
CY2014Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	175300000	USD
CY2014Q4	nu	Uncollectible Hardship Accounts Receivable Reserve UncollectibleHardshipAccountsReceivableReserve	91500000	USD
CY2013Q4	nu	Uncollectible Hardship Accounts Receivable Reserve UncollectibleHardshipAccountsReceivableReserve	81200000	USD
CY2014Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	3200000	USD
CY2013Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	1700000	USD
CY2013Q4	nu	Cash Collateral Deposited CashCollateralDeposited	17900000	USD
CY2014Q4	nu	Cash Collateral Deposited CashCollateralDeposited	9900000	USD
CY2014	nu	Fuel Power Costs FuelPowerCosts	599400000	USD
CY2013	nu	Fuel Power Costs FuelPowerCosts	466500000	USD
CY2012	nu	Fuel Power Costs FuelPowerCosts	346800000	USD
CY2014	us-gaap	Interest Paid Net InterestPaidNet	349600000	USD
CY2013	us-gaap	Interest Paid Net InterestPaidNet	343300000	USD
CY2014	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	-5800000	USD
CY2014	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	13700000	USD
CY2014	nu	Public Utilities Allowance For Funds Used During Construction Capitalized Total PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedTotal	19500000	USD
CY2013	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	-4100000	USD
CY2013	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	7100000	USD
CY2013	nu	Public Utilities Allowance For Funds Used During Construction Capitalized Total PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedTotal	11200000	USD
CY2012	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	-5300000	USD
CY2012	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	6800000	USD
CY2012	nu	Public Utilities Allowance For Funds Used During Construction Capitalized Total PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedTotal	12100000	USD
CY2014	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.034	pure
CY2013	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.027	pure
CY2012	us-gaap	Public Utilities Allowance For Funds Used During Construction Rate PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate	0.037	pure
CY2014	us-gaap	Excise And Sales Taxes ExciseAndSalesTaxes	148200000	USD
CY2013	us-gaap	Excise And Sales Taxes ExciseAndSalesTaxes	144100000	USD
CY2012	us-gaap	Excise And Sales Taxes ExciseAndSalesTaxes	135000000	USD
CY2014	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	181900000	USD
CY2013	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	193100000	USD
CY2012	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	160600000	USD
CY2012	us-gaap	Interest Paid Net InterestPaidNet	356500000	USD
CY2012	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-12800000	USD
CY2013	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	50000000	USD
CY2014	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	334200000	USD
CY2014	us-gaap	Description Of Postemployment Benefits DescriptionOfPostemploymentBenefits	For the years ended December 31, 2014 and 2013, NU recorded severance benefit expenses of $15 million and $9.7 million, respectively, in connection with the partial outsourcing of information technology functions and facilities closures, as well as ongoing post-merger integration. As of December 31, 2014 and 2013, the severance accrual totaled $10.4 million and $14.7 million, respectively, and was included in Other Current Liabilities on the balance sheets.
CY2013	us-gaap	Postemployment Benefits Period Expense PostemploymentBenefitsPeriodExpense	9700000	USD
CY2013Q4	us-gaap	Postemployment Benefits Liability Current PostemploymentBenefitsLiabilityCurrent	14700000	USD
CY2014	us-gaap	Postemployment Benefits Period Expense PostemploymentBenefitsPeriodExpense	15000000	USD
CY2014Q4	us-gaap	Postemployment Benefits Liability Current PostemploymentBenefitsLiabilityCurrent	10400000	USD
CY2014Q4	nu	Electric And Natural Gas Utility Accumulated Depreciation ElectricAndNaturalGasUtilityAccumulatedDepreciation	5777800000	USD
CY2014Q4	us-gaap	Regulatory Assets RegulatoryAssets	4726600000	USD
CY2013Q4	us-gaap	Regulatory Assets RegulatoryAssets	4294500000	USD
CY2014Q4	us-gaap	Amount Of Regulatory Costs Not Yet Approved AmountOfRegulatoryCostsNotYetApproved	60500000	USD
CY2013Q4	us-gaap	Amount Of Regulatory Costs Not Yet Approved AmountOfRegulatoryCostsNotYetApproved	65100000	USD
CY2014	us-gaap	Description Of Regulatory Assets And Liabilities DescriptionOfRegulatoryAssetsAndLiabilities	Regulatory Assets - The following provides further information about regulatory assets: Benefit Costs: NU's Pension, SERP and PBOP Plans are accounted for in accordance with accounting guidance on defined benefit pension and other PBOP plans. The liability recorded by the Regulated companies to recognize the funded status of their retiree benefit plans are offset by regulatory assets in lieu of a charge to Accumulated Other Comprehensive Income/(Loss), reflecting ultimate recovery from customers through rates. All amounts are remeasured annually. Regulatory accounting was also applied to the portions of NU's service company costs that support the Regulated companies, as these amounts are also recoverable. As these regulatory assets do not represent a cash outlay for the Regulated companies, no carrying charge is recovered from customers. The increase in the funded status liability of the retiree benefit plans and the corresponding regulatory assets was primarily driven by a change in mortality assumptions, which increased the estimate of benefits to be provided to plan participants, and a decrease in the discount rate assumption. For further information on the funded status liability and related regulatory assets of the Pension, SERP and PBOP plans, see Note 9A, "Employee Benefits – Pension Benefits and Postretirement Benefits Other Than Pensions." CL&P, NSTAR Electric, PSNH and WMECO recover benefit costs related to their distribution and transmission operations from customers in rates as allowed by their applicable regulatory commissions. NSTAR Electric and WMECO each recover their qualified pension and PBOP expenses related to distribution operations through rate reconciling mechanisms that fully track the change in net pension and PBOP expenses each year. Derivative Liabilities: Regulatory assets recorded as an offset to derivative liabilities relate to the fair value of contracts used to purchase energy and energy-related products that will be recovered from customers in future rates. See Note 4, "Derivative Instruments," to the financial statements for further information.  These assets are excluded from rate base and are being recovered as the actual settlements occur over the duration of the contracts. Income Taxes, Net: The tax effect of temporary book-tax 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. As these assets are offset by deferred income tax liabilities, no carrying charge is collected. For further information regarding income taxes, see Note 10, "Income Taxes," to the financial statements. Storm Restoration Costs: The storm restoration cost deferrals relate to costs incurred at CL&P, NSTAR Electric, PSNH and WMECO that each company expects to recover from customers. A storm must meet certain criteria to be declared a major storm with the criteria specific to each state jurisdiction and utility company. Once a storm is declared major, all qualifying expenses incurred during storm restoration efforts are deferred and recovered from customers. In addition to storm restoration costs, CL&P and PSNH are each allowed to recover storm pre-staging costs in accordance with applicable regulation. CL&P, NSTAR Electric, PSNH and WMECO experienced several significant storm events, including Tropical Storm Irene in 2011, the October 2011 snowstorm, Storm Sandy in 2012 and the February 2013 blizzard. As a result of these storm events, each company suffered extensive damage to its distribution and transmission systems resulting in customer outages. Each company incurred significant costs to repair damage and restore customers' service. In addition, on November 26, 2014, a snowstorm caused damage to the electric delivery systems of PSNH and WMECO. This snowstorm resulted in estimated deferred storm restoration costs of approximately $23 million at PSNH and approximately $3 million at WMECO. The storm restoration cost regulatory asset balance at CL&P, NSTAR Electric, PSNH and WMECO reflects deferrable costs incurred for major storm events. Management believes the storm restoration costs were prudent and meet the criteria for specific cost recovery in Connecticut, Massachusetts and New Hampshire, and that recovery from customers is probable through the applicable regulatory recovery process. Storm Filings: Each electric utility has sought, or is seeking, recovery of its deferred storm restoration costs through its applicable regulatory recovery process. CL&P: As of December 31, 2014, all CL&P deferred storm costs have been reviewed and approved for recovery in distribution rates. On March 12, 2014, the PURA approved recovery of $365 million of deferred storm restoration costs (with carrying charges) associated with five major storms that occurred in 2011 and 2012 and ordered CL&P to capitalize approximately $18 million of the deferred storm restoration costs as utility plant, which will be recovered through depreciation expense in future rate proceedings. CL&P will recover the $365 million in its distribution rates over a six-year period that commenced on December 1, 2014. The remaining costs were either disallowed or are probable of recovery from other sources. These costs did not have a material impact on CL&P’s financial position, results of operations or cash flows. Effective June 1, 2014, CL&P received $65.4 million of DOE Phase II Damages proceeds. On June 17, 2014, the PURA ordered CL&P to refund these proceeds to customers by offsetting the deferred storm restoration costs regulatory asset. For further information on the DOE Phase II Damages proceeds received from the Yankee Companies, see Note 11C, "Commitments and Contingencies - Contractual Obligations - Yankee Companies," to the financial statements. On December 17, 2014, as part of the distribution rate case decision, CL&P was also allowed recovery of the 2013 storm costs and residual 2012 Storm Sandy costs over a seven-year period that commenced on December 1, 2014. NSTAR Electric: On December 30, 2013, the DPU approved recovery of $34.2 million of NSTAR Electric’s storm restoration costs, plus carrying costs, related to Tropical Storm Irene in 2011 and the October 2011 snowstorm. NSTAR Electric is recovering these costs, plus carrying costs, in its distribution rates over a five-year period that commenced on January 1, 2014. PSNH: On June 27, 2013, the NHPUC approved an increase to PSNH’s distribution rates effective July 1, 2013, which included a $5 million increase to the level of funding for the major storm cost reserve. The major storm cost reserve is used to offset the storm restoration cost regulatory asset. On April 7, 2014, PSNH received an audit report from the NHPUC approving storm costs from 2011 through March 2013. WMECO: On December 20, 2013, the DPU approved WMECO's 2013 Annual Storm Reserve Recovery Cost Adjustment filing to begin recovering the October 2011 snowstorm and 2012 Storm Sandy restoration costs, which commenced on January 1, 2014, subject to further review and reconciliation. On December 5, 2014, the DPU approved the majority of deferred storm costs through 2011. Goodwill-related: The goodwill regulatory asset originated from the transaction that created NSTAR in 1999. This regulatory asset is currently being amortized and recovered from customers in rates without a carrying charge over a 40-year period (as of December 31, 2014, there were 25 years of amortization remaining). Regulatory Tracker Mechanisms: The Regulated companies’ approved rates are designed to recover their incurred costs to provide service to customers. The Regulated companies recover certain of their costs on a fully-reconciling basis through regulatory commission-approved tracking mechanisms. The difference between the costs incurred (or the rate recovery allowed) and the actual revenues is recorded as regulatory assets (for undercollections) or regulatory liabilities (for overcollections) to be included in future customer rates each year. Carrying charges are recorded on all material regulatory tracker mechanisms. CL&P, NSTAR Electric, PSNH and WMECO each recover the costs associated with the procurement of energy, transmission related costs from FERC-approved transmission tariffs, energy efficiency programs, low income assistance programs, and restructuring and stranded costs as a result of deregulation, on a fully reconciling basis. Energy procurement costs at PSNH include the costs related to its generating stations. WMECO's and CL&P's (effective December 1, 2014) distribution revenue is decoupled from their customer sales volume. CL&P and WMECO reconcile their annual base distribution rate recovery to a pre-established level of baseline distribution delivery service revenue. Any difference between the allowed level of distribution revenue and the actual amount incurred during a 12-month period is adjusted through rates in the following period. Contractual Obligations - Yankee Companies: CL&P, NSTAR Electric, PSNH and WMECO are responsible for their proportionate share of the remaining costs of the CYAPC, YAEC and MYAPC nuclear facilities, including nuclear fuel storage. A portion of these amounts was recorded as a regulatory asset. Amounts for CL&P are earning a return and are being recovered through the CTA. Amounts for NSTAR Electric and WMECO are being recovered without a return through the transition charge. Amounts for PSNH were fully recovered in 2006. As a result of NU's consolidation of CYAPC and YAEC, NU's regulatory asset balance also includes the regulatory assets of CYAPC and YAEC, which totaled $97.8 million and $129.8 million as of December 31, 2014 and 2013, respectively. Intercompany transactions between CL&P, NSTAR Electric, PSNH and WMECO and the CYAPC and YAEC companies have been eliminated in consolidation of the NU financial statements. Buy Out Agreements for Power Contracts: NSTAR Electric's balance represents the contract termination liability related to certain purchase power contract buy out agreements that were executed in 2004. The contracts’ termination payments occur through September 2016 and are collected from customers through NSTAR Electric’s transition charge over the same period. NSTAR Electric does not earn a return on this regulatory asset. PSNH's balance represents payments associated with the termination of various power purchase contracts that were recorded as regulatory assets and are amortized over the remaining life of the contracts. Other Regulatory Assets: Other Regulatory Assets primarily include asset retirement obligations, environmental remediation costs, losses associated with the reacquisition or redemption of long-term debt and various other items, partially offset by purchase price adjustments recorded as Regulatory Assets in connection with the merger with NSTAR. Regulatory Liabilities: The components of regulatory liabilities are as follows: 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. The estimated cost to remove utility assets from service is recognized as a component of depreciation expense and the cumulative amounts collected from customers but not yet expended is recognized as a regulatory liability. Expended costs that exceed amounts collected from customers are recognized as regulatory assets, as they are probable of recovery in future rates. AFUDC - Transmission: AFUDC was recorded by CL&P and WMECO 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. NSTAR Electric recorded AFUDC on reliability-related projects over $5 million through December 31, 2014, 50 percent of which was recorded as a regulatory liability to reflect rate base recovery for 50 percent of the CWIP as a result of FERC-approved transmission incentives. Other Regulatory Liabilities: Other Regulatory Liabilities primarily includes amounts that are subject to various rate reconciling mechanisms that, as of each period end date, would result in refunds to customers. 2014 Regulatory Developments: As a result of actions taken by the FERC and other developments in the pending base ROE complaint proceedings described in Note 11E, "Commitments and Contingencies – FERC Base ROE Complaints," in 2014 the Company recorded reserves at its electric subsidiaries to recognize the potential financial impact of the first and second complaints. As of December 31, 2014, the cumulative pre-tax reserves (excluding interest), which exclude refunds for the first complaint refund period, totaled $60.7 million at NU, $33.5 million at CL&P, $13.6 million at NSTAR Electric, $5.1 million at PSNH and $8.5 million at WMECO. As of December 31, 2013, as a result of the 2013 FERC ALJ initial decision, the Company had an aggregate pre-tax reserve (excluding interest) of $23.7 million at NU, $12.8 million at CL&P, $5.7 million at NSTAR Electric, $2.3 million at PSNH and $2.9 million at WMECO. These reserves were recorded as a regulatory liability in Regulatory Tracker Mechanisms and as a reduction of Operating Revenues. Effective June 1, 2014, as a result of damages awarded to the Yankee Companies for spent nuclear fuel lawsuits against the DOE described in Note 11C, "Commitments and Contingencies - Contractual Obligations - Yankee Companies," the Yankee Companies returned the DOE Phase II Damages proceeds to the member companies, including CL&P, NSTAR Electric, PSNH, and WMECO, for the benefit of their respective customers. CL&P's refund obligation to customers of $65.4 million was recorded as an offset to the deferred storm restoration costs regulatory asset, as directed by PURA. NSTAR Electric's, PSNH's and WMECO's refund obligation to customers of $29.1 million, $13.1 million and $18.1 million, respectively, was recorded as a regulatory liability in Regulatory Tracker Mechanisms. Refunds to customers for these DOE proceeds began in 2014. On December 31, 2014, NSTAR Electric, NSTAR Gas and the Massachusetts Attorney General filed a comprehensive settlement agreement with the DPU. The comprehensive settlement agreement included resolution of the outstanding NSTAR Electric CPSL program filings for the periods 2006 through 2011, the NSTAR Electric and NSTAR Gas PAM and energy efficiency-related customer billing adjustments reported in 2012, and the NSTAR Electric energy efficiency program filings regarding LBR for the periods 2008 through 2011. If approved by the DPU, NSTAR Electric and NSTAR Gas will be required to refund a total of $44.7 million to their respective customers, which was included in Regulatory Tracker Mechanisms and Other Regulatory Liabilities as of December 31, 2014. For further information, see Note 11F, "Commitments and Contingencies – 2014 Comprehensive Settlement Agreement."
CY2014Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	750100000	USD
CY2013Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	707300000	USD
CY2014	us-gaap	Property Plant And Equipment Depreciation Methods PropertyPlantAndEquipmentDepreciationMethods	Utility property, plant and equipment is recorded at original cost. Original cost includes materials, labor, construction overhead and AFUDC for regulated property. The cost of repairs and maintenance, including planned major maintenance activities, is charged to Operating Expenses as incurred. Depreciation of utility assets is calculated on a straight-line basis using composite rates based on the estimated remaining useful lives of the various classes of property (estimated useful life for PSNH distribution). The composite rates are subject to approval by the appropriate state regulatory agency. The composite rates include a cost of removal component, which is collected from customers over the lives of the plant assets and is recognized as a regulatory liability. Depreciation rates are applied to property from the time it is placed in service. Upon retirement from service, the cost of the utility asset is charged to the accumulated provision for depreciation. The actual incurred removal costs are applied against the related regulatory liability.
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	12495200000	USD
CY2014Q4	nu	Public Utilities Property Plant And Equipment Distribution Natural Gas PublicUtilitiesPropertyPlantAndEquipmentDistributionNaturalGas	2595400000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	6930700000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Generation Or Processing PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing	1170900000	USD
CY2014Q4	nu	Public Utilities Property Plant And Equipment Electric And Natural Gas Utility Total PublicUtilitiesPropertyPlantAndEquipmentElectricAndNaturalGasUtilityTotal	23192200000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	551300000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	23743500000	USD
CY2014Q4	nu	Other Accumulated Depreciation OtherAccumulatedDepreciation	231800000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	6009600000	USD
CY2014Q4	nu	Property Plant And Equipment Net Excluding Construction Work In Progress PropertyPlantAndEquipmentNetExcludingConstructionWorkInProgress	17733900000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	913100000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	11950200000	USD
CY2013Q4	nu	Public Utilities Property Plant And Equipment Distribution Natural Gas PublicUtilitiesPropertyPlantAndEquipmentDistributionNaturalGas	2425900000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	6412500000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Generation Or Processing PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing	1152300000	USD
CY2013Q4	nu	Public Utilities Property Plant And Equipment Electric And Natural Gas Utility Total PublicUtilitiesPropertyPlantAndEquipmentElectricAndNaturalGasUtilityTotal	21940900000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	508700000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	22449600000	USD
CY2013Q4	nu	Electric And Natural Gas Utility Accumulated Depreciation ElectricAndNaturalGasUtilityAccumulatedDepreciation	5387000000	USD
CY2013Q4	nu	Other Accumulated Depreciation OtherAccumulatedDepreciation	196200000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	5583200000	USD
CY2013Q4	nu	Property Plant And Equipment Net Excluding Construction Work In Progress PropertyPlantAndEquipmentNetExcludingConstructionWorkInProgress	16866400000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	709800000	USD
CY2014	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.030	pure
CY2013	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.028	pure
CY2012	us-gaap	Public Utilities Property Plant And Equipment Disclosure Of Composite Depreciation Rate For Plants In Service PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService	0.025	pure
CY2014Q4	nu	Distribution Assets Average Useful Life DistributionAssetsAverageUsefulLife	34.9	pure
CY2014Q4	nu	Transmission Assets Average Useful Life TransmissionAssetsAverageUsefulLife	42.5	pure
CY2014Q4	nu	Generation Assets Average Useful Life GenerationAssetsAverageUsefulLife	31.9	pure
CY2014Q4	nu	Other Assets Average Useful Life OtherAssetsAverageUsefulLife	14.2	pure
CY2014	us-gaap	Description Of Derivative Activity Volume DescriptionOfDerivativeActivityVolume	Commodity Supply and Price Risk Management: As required by regulation, CL&P, along with UI, has capacity-related contracts with generation facilities. CL&P has a sharing agreement with UI, with 80 percent of each contract allocated to CL&P and 20 percent allocated to UI. The combined capacity of these contracts is 787 MW. The capacity contracts extend through 2026 and obligate both CL&P and UI to make or receive payments on a monthly basis to or from the generation facilities based on the difference between a set capacity price and the capacity market price received in the ISO-NE capacity markets. In addition, CL&P has a contract to purchase 0.1 million MWh of energy per year through 2020. NSTAR Electric has a renewable energy contract to purchase 0.1 million MWh of energy per year through 2018 and a capacity-related contract to purchase up to 35 MW per year through 2019. As of December 31, 2014 and 2013, NU had NYMEX future contracts in order to reduce variability associated with the purchase price of approximately 8.8 million and 9.1 million MMBtu of natural gas, respectively.
CY2014Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	10000000	USD
CY2014Q4	us-gaap	Additional Collateral Aggregate Fair Value AdditionalCollateralAggregateFairValue	10000000	USD
CY2014	nu	Fairvalueinputsexitpricepremium Fairvalueinputsexitpricepremium	Exit price premiums of 7 percent through 24 percent are also applied on these contracts and reflect the most recent market activity available for similar type contracts.
CY2012Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	878600000	USD
CY2013	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	74200000	USD
CY2013Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	635200000	USD
CY2014Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	415400000	USD
CY2014	nu	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Gain Loss Included In Reg Asset Liability FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityGainLossIncludedInRegAssetLiability	141300000	USD
CY2014	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	78500000	USD
CY2013	nu	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Gain Loss Included In Reg Asset Liability FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityGainLossIncludedInRegAssetLiability	158300000	USD
CY2013	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	10900000	USD
CY2014Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	313000000	USD
CY2014Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	55000000	USD
CY2014Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	66000000	USD
CY2014Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	103200000	USD
CY2013Q4	nu	Fair Value Of Securities Under Fair Value Option FairValueOfSecuritiesUnderFairValueOption	57200000	USD
CY2014Q4	nu	Fair Value Of Securities Under Fair Value Option FairValueOfSecuritiesUnderFairValueOption	85100000	USD
CY2014	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	1900000	USD
CY2013	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	10200000	USD
CY2012	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	5900000	USD
CY2014Q4	us-gaap	Marketable Securities Restricted Noncurrent MarketableSecuritiesRestrictedNoncurrent	450800000	USD
CY2013Q4	us-gaap	Marketable Securities Restricted Noncurrent MarketableSecuritiesRestrictedNoncurrent	424000000	USD
CY2014Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	55000000	USD
CY2014Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	88800000	USD
CY2014Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	89100000	USD
CY2014Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	67700000	USD
CY2014Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	108400000	USD
CY2014Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	320200000	USD
CY2014Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	639200000	USD
CY2013Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	580900000	USD
CY2014	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	-19500000	USD
CY2014	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	25100000	USD
CY2014	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	-5500000	USD
CY2014Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	426300000	USD
CY2012Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	412200000	USD
CY2013	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	100000	USD
CY2013	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	23800000	USD
CY2013	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	2600000	USD
CY2013Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	424900000	USD
CY2013	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	-13800000	USD
CY2014	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	1300000	USD
CY2014	nu	Short Term Debt Regulatory Limits ShortTermDebtRegulatoryLimits	The amount of short-term borrowings that may be incurred by CL&P, NSTAR Electric 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 July 31, 2013, the FERC granted authorization to allow CL&P and WMECO to incur total short-term borrowings up to a maximum of $600 million and $300 million, respectively, effective January 1, 2014 through December 31, 2015. On June 11, 2014, the FERC granted authorization to allow NSTAR Electric to issue total short-term debt securities in an aggregate principal amount not to exceed $655 million outstanding at any one time, effective October 24, 2014 through October 23, 2016. 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. As of December 31, 2014, CL&P had $432.1 million of unsecured debt capacity available under this authorization.
CY2013	nu	Description Of St Debt Reclassified To Lt DescriptionOfStDebtReclassifiedToLt	On January 2, 2014, Yankee Gas issued $100 million of Series L First Mortgage Bonds and $25 million of the proceeds was used to repay short-term borrowings outstanding under the NU commercial paper program. As the debt issuance refinanced short-term debt, these amounts were classified as Long-Term Debt on NU's balance sheet as of December 31, 2013.
CY2014	us-gaap	Line Of Credit Facility Description LineOfCreditFacilityDescription	Credit Agreements and Commercial Paper Programs: NU parent, CL&P, PSNH, WMECO, NSTAR Gas and Yankee Gas are parties to a five-year $1.45 billion revolving credit facility. The revolving credit facility is to be used primarily to backstop NU parent's $1.45 billion commercial paper program. The commercial paper program allows NU parent to issue commercial paper as a form of short-term debt. Effective July 23, 2014, NU parent, CL&P, PSNH, WMECO, NSTAR Gas and Yankee Gas extended the expiration date of their joint revolving credit facility for one additional year to September 6, 2019. CL&P has a borrowing sublimit of $600 million and PSNH and WMECO each have borrowing sublimits of $300 million. As of December 31, 2014 and 2013, NU had approximately $1.1 billion and $1.01 billion, respectively, in short-term borrowings outstanding under the NU parent commercial paper program, leaving $348.9 million and $435.5 million of available borrowing capacity as of December 31, 2014 and 2013, respectively. The weighted-average interest rate on these borrowings as of December 31, 2014 and 2013 was 0.43 percent and 0.24 percent, respectively, which is generally based on A2/P2 rated commercial paper. As of December 31, 2014, there were intercompany loans from NU of $133.4 million to CL&P, $90.5 million to PSNH and $21.4 million to WMECO. As of December 31, 2013, there were intercompany loans from NU of $287.3 million to CL&P and $86.5 million to PSNH. NSTAR Electric has a five-year $450 million revolving credit facility. This facility serves to backstop NSTAR Electric’s existing $450 million commercial paper program. Effective July 23, 2014, NSTAR Electric extended the expiration date of its revolving credit facility for one additional year to September 6, 2019. As of December 31, 2014 and 2013, NSTAR Electric had $302 million and $103.5 million, respectively, in short-term borrowings outstanding under its commercial paper program, leaving $148 million and $346.5 million of available borrowing capacity as of December 31, 2014 and 2013, respectively. The weighted-average interest rate on these borrowings as of December 31, 2014 and 2013 was 0.27 percent and 0.13 percent, respectively, which is generally based on A2/P1 rated commercial paper.
CY2014	nu	Description Of St Debt Reclassified To Lt DescriptionOfStDebtReclassifiedToLt	On January 15, 2015, NU parent issued $150 million of 1.60 percent Series G Senior Notes due to mature in 2018 and $300 million of 3.15 percent Series H Senior Notes, due to mature in 2025. The proceeds, net of issuance costs, were used to repay short-term borrowings outstanding under the NU commercial paper program. As the debt issuances refinanced short-term debt, the short-term debt was classified as Long-Term Debt as of December 31, 2014.
CY2014	us-gaap	Long Term Debt Description LongTermDebtDescription	On September 15, 2014, CL&P repaid at maturity the $150 million of 4.80 percent 2004 Series A First Mortgage Bonds, using short-term borrowings. On April 24, 2014, CL&P issued $250 million of 4.30 percent 2014 Series A First Mortgage Bonds, due to mature in 2044. The proceeds, net of issuance costs, were used to repay short-term borrowings. On February 12, 2015, CL&P notified the trustee that it intends to purchase and cancel the bonds on April 1, 2015, after they have been tendered by the bondholders. On March 7, 2014, NSTAR Electric issued $300 million of 4.40 percent debentures, due to mature in 2044. The proceeds, net of issuance costs, were used to repay the $300 million of 4.875 percent debentures that matured on April 15, 2014. As of December 31, 2014 and 2013, the interest rate was 0.4721 percent and 0.478 percent, respectively. On July 15, 2014, PSNH repaid at maturity the $50 million of 5.25 percent Series L First Mortgage Bonds using short-term borrowings. On October 14, 2014, PSNH issued $75 million of first mortgage bonds at a yield of 3.144 percent due to mature in 2023. The first mortgage bonds are part of the same series of PSNH’s existing 3.50 percent Series S First Mortgage Bonds that were initially issued in November 2013. The proceeds, net of issuance costs, were used to repay short-term borrowings. On January 2, 2014, Yankee Gas issued $100 million of 4.82 percent Series L First Mortgage Bonds, due to mature in 2044. The proceeds, net of issuance costs, were used to repay the $75 million 4.80 percent Series G First Mortgage Bonds that matured on January 1, 2014 and to pay $25 million in short-term borrowings. As the debt issuance refinanced short-term debt, these amounts were classified as Long-Term Debt on NU's balance sheet as of December 31, 2013. On January 15, 2015, NU parent issued $150 million of 1.60 percent Series G Senior Notes due to mature in 2018 and $300 million of 3.15 percent Series H Notes, due to mature in 2025. The proceeds, net of issuance costs, were used to repay short-term borrowings outstanding under the NU commercial paper program. As the debt issuances refinanced short-term debt, the short-term debt was classified as Long-Term Debt as of December 31, 2014. Amount relates to the purchase price adjustment required to record the NSTAR long-term debt at fair value on the date of the merger. On July 15, 2014, PSNH repaid at maturity the $50 million of 5.25 percent Series L First Mortgage Bonds using short-term borrowings. On October 14, 2014, PSNH issued $75 million of first mortgage bonds at a yield of 3.144 percent due to mature in 2023. The first mortgage bonds are part of the same series of PSNH’s existing 3.50 percent Series S First Mortgage Bonds that were initially issued in November 2013. The proceeds, net of issuance costs, were used to repay short-term borrowings. 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. In addition, as a result of consolidating CYAPC, NU has consolidated $179.4 million in additional spent nuclear fuel obligations, including interest, as of both December 31, 2014 and 2013. The obligation due to the DOE for the disposal of CL&P's and WMECO's Prior Period Spent Nuclear Fuel and CYAPC's spent nuclear fuel obligation include accumulated interest costs of $350.4 million and $350.3 million ($178 million and $177.9 million for CL&P and $41.8 million and $41.7 million for WMECO) as of December 31, 2014 and 2013, respectively.
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	216700000	USD
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	200000000	USD
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	745000000	USD
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	810000000	USD
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	800000000	USD
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	4956600000	USD
CY2014Q4	nu	Longtermdebtmaturitiesrepaymentsofprincipaltotal Longtermdebtmaturitiesrepaymentsofprincipaltotal	7728300000	USD
CY2014	us-gaap	Defined Benefit Plan Estimated Future Employer Contributions In Next Fiscal Year Description DefinedBenefitPlanEstimatedFutureEmployerContributionsInNextFiscalYearDescription	NU expects to make contributions of approximately $155 million in 2015, of which $5 million will be contributed by NSTAR Electric and $1 million will be contributed by PSNH. The remaining $149 million is expected to be contributed by other NU subsidiaries, primarily NUSCO. NU contributed $40 million to the PBOP Plans in 2014 and expects to make approximately $27 million in contributions in 2015. This amount will be funded into the 401(h) account and VEBAs up to the maximum tax-deductible level permitted
CY2014	nu	Description Of Allocation Of Assets To Subsidiaries DescriptionOfAllocationOfAssetsToSubsidiaries	Effective January 1, 2013, the NSTAR Pension Plan assets were transferred into the NUSCO Pension Plan master trust. The NUSCO Pension Plan is entitled to approximately 66 percent of each asset category in the master trust, the NSTAR Pension Plan is entitled to approximately 30 percent of each asset category in the master trust and the 401(h) plans are entitled to approximately four percent of each asset category in the master trust. For the years ended December 31, 2014 and 2013 the NUSCO Pension Plan was entitled to $2,803.6 million and $2,750.4 million respectively and the NSTAR Pension Plan was entitled to $1,322.9 million and $1,235.3 million, respectively. Also effective January 1, 2013, the NSTAR PBOP Plan assets were transferred into a master trust with the NUSCO PBOP Plan assets and assets were allocated to each plan. For the years ended December 31, 2014 and 2013, the NUSCO PBOP Plan was entitled to $399 million and $391 million, respectively, and the NSTAR PBOP Plan was entitled to $463.6 million and $435.5 million, respectively. CL&P, PSNH and WMECO are allocated a portion of the NUSCO Pension and PBOP Plan assets. NSTAR Electric is entitled to a portion of the NSTAR Pension and PBOP Plan assets.
CY2014	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	29700000	USD
CY2013	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	37000000	USD
CY2012	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	25700000	USD
CY2013	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	9100000	USD
CY2012	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	8900000	USD
CY2012Q2	nu	Share Based Compensation Arrangement By Share Based Payment Award Options Converted Nstar Options Upon Merger ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConvertedNstarOptionsUponMerger	2664894	shares
CY2012Q2	nu	Share Based Compensation Arrangement By Share Based Payment Award Options Converted Nstar Options Upon Merger Total Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConvertedNstarOptionsUponMergerTotalValue	30.5	USD
CY2012Q2	nu	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nstar Deferred And Performance Awards Converted Upon Merger ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNstarDeferredAndPerformanceAwardsConvertedUponMerger	421775	shares
CY2012Q2	nu	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nstar Deferred And Performance Awards Converted Upon Merger Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNstarDeferredAndPerformanceAwardsConvertedUponMergerValue	15.5	USD
CY2012Q2	nu	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nstar Rsu Retention Awards Converted To Nu Rsus Upon Merger ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNstarRsuRetentionAwardsConvertedToNuRsusUponMerger	195619	shares
CY2012Q2	nu	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nstar Rsu Retention Awards Converted To Nu Rsus Upon Merger Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNstarRsuRetentionAwardsConvertedToNuRsusUponMergerValue	7.2	USD
CY2014Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	8000000	shares
CY2014Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	3112020	shares
CY2013Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	3440590	shares
CY2014Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	1024729	shares
CY2013Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	1162216	shares
CY2014Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	38.14
CY2013Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	36.58
CY2014	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	437887	shares
CY2014	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue	37.36
CY2014	nu	Share Based Compensation Arrangement By Share Based Payment Award Vested Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardVestedOutstandingNumber	356018	shares
CY2014	nu	Share Based Compensation Arrangement By Share Based Payment Award Expected To Vest ShareBasedCompensationArrangementByShareBasedPaymentAwardExpectedToVest	973493	shares
CY2014	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	24600000	USD
CY2013	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	27000000	USD
CY2012	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	25800000	USD
CY2014	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	10300000	USD
CY2013	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	10700000	USD
CY2012	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	10200000	USD
CY2014	nu	Description Of Compensation Cost Not Yet Recognized Period For Recognition DescriptionOfCompensationCostNotYetRecognizedPeriodForRecognition	This cost is expected to be recognized ratably over a weighted-average period of 1.65 years for NU, 1.68 years for CL&P, 1.69 years for NSTAR Electric, 1.71 years for PSNH and 1.68 years for WMECO.
CY2011Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	47374	shares
CY2013	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	-324382	shares
CY2013Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	1221375	shares
CY2011Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	18.78
CY2013Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	25.97
CY2013	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	20.97
CY2013	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	6700000	USD
CY2014Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	15700000	USD
CY2012Q2	nu	Share Based Compensation Arrangement By Share Based Payment Award Options Converted Nstar Options Upon Merger Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConvertedNstarOptionsUponMergerWeightedAverageExercisePrice	23.99
CY2012	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	-1166511	shares
CY2012	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	22.53
CY2012	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	18700000	USD
CY2012Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	1545757	shares
CY2012Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	24.92
CY2014	us-gaap	Employee Service Share Based Compensation Cash Received From Exercise Of Stock Options EmployeeServiceShareBasedCompensationCashReceivedFromExerciseOfStockOptions	22300000	USD
CY2014	us-gaap	Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOptions	6600000	USD
CY2014	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	40779	shares
CY2013	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	39526	shares
CY2014	nu	Espp Discounted Purchase Price First Six Months EsppDiscountedPurchasePriceFirstSixMonths	41.61	USD
CY2014	nu	Espp Discounted Purchase Price Second Six Months EsppDiscountedPurchasePriceSecondSixMonths	41.71	USD
CY2013	nu	Espp Discounted Purchase Price First Six Months EsppDiscountedPurchasePriceFirstSixMonths	38.69	USD
CY2013	nu	Espp Discounted Purchase Price Second Six Months EsppDiscountedPurchasePriceSecondSixMonths	42.19	USD
CY2014Q4	nu	Employee Stock Purchase Plan Shares Remaining For Future Issuance EmployeeStockPurchasePlanSharesRemainingForFutureIssuance	776975	shares
CY2013Q4	nu	Employee Stock Purchase Plan Shares Remaining For Future Issuance EmployeeStockPurchasePlanSharesRemainingForFutureIssuance	817754	shares
CY2014	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	-869759	shares
CY2014	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	25.68
CY2014Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	351616	shares
CY2014Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	26.69
CY2014Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	9400000	USD
CY2014	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	16400000	USD
CY2013	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	-3700000	USD
CY2013	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	27600000	USD
CY2014Q4	us-gaap	Deferred Compensation Cashbased Arrangements Liability Classified Noncurrent DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent	57500000	USD
CY2013Q4	us-gaap	Deferred Compensation Cashbased Arrangements Liability Classified Noncurrent DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent	51300000	USD
CY2012Q4	us-gaap	Deferred Compensation Cashbased Arrangements Liability Classified Noncurrent DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent	54600000	USD
CY2014Q4	nu	Deferred Compensation Cash Based Arrangements Expense Pertaining To Deferred Benefits DeferredCompensationCashBasedArrangementsExpensePertainingToDeferredBenefits	4500000	USD
CY2013Q4	nu	Deferred Compensation Cash Based Arrangements Expense Pertaining To Deferred Benefits DeferredCompensationCashBasedArrangementsExpensePertainingToDeferredBenefits	4400000	USD
CY2012Q4	nu	Deferred Compensation Cash Based Arrangements Expense Pertaining To Deferred Benefits DeferredCompensationCashBasedArrangementsExpensePertainingToDeferredBenefits	4700000	USD
CY2014	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	4400000	USD
CY2013	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	8800000	USD
CY2012	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-30900000	USD
CY2012	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	17600000	USD
CY2013	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-9400000	USD
CY2014	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	24500000	USD
CY2014	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	28900000	USD
CY2013	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-600000	USD
CY2012	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-13300000	USD
CY2012	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	291300000	USD
CY2013	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	386200000	USD
CY2014	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	406800000	USD
CY2014	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	36500000	USD
CY2013	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	45400000	USD
CY2012	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	800000	USD
CY2012	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	-3900000	USD
CY2013	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	-4100000	USD
CY2014	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	-3900000	USD
CY2014	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	453400000	USD
CY2014	us-gaap	Income Tax Reconciliation Nondeductible Expense Depreciation IncomeTaxReconciliationNondeductibleExpenseDepreciation	-5600000	USD
CY2014	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	-3500000	USD
CY2014	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	42500000	USD
CY2014	us-gaap	Income Tax Rate Reconciliation Deductions Employee Stock Ownership Plan Dividends IncomeTaxRateReconciliationDeductionsEmployeeStockOwnershipPlanDividends	-8000000	USD
CY2014	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-2900000	USD
CY2014	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-3700000	USD
CY2013	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	427200000	USD
CY2013	us-gaap	Income Tax Reconciliation Nondeductible Expense Depreciation IncomeTaxReconciliationNondeductibleExpenseDepreciation	-7400000	USD
CY2013	us-gaap	Income Tax Rate Reconciliation Deductions Employee Stock Ownership Plan Dividends IncomeTaxRateReconciliationDeductionsEmployeeStockOwnershipPlanDividends	-8000000	USD
CY2013	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-4300000	USD
CY2013	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-400000	USD
CY2012	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	282800000	USD
CY2012	us-gaap	Income Tax Reconciliation Nondeductible Expense Depreciation IncomeTaxReconciliationNondeductibleExpenseDepreciation	-10800000	USD
CY2012	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	-3800000	USD
CY2012	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	4400000	USD
CY2012	us-gaap	Income Tax Rate Reconciliation Deductions Employee Stock Ownership Plan Dividends IncomeTaxRateReconciliationDeductionsEmployeeStockOwnershipPlanDividends	-6400000	USD
CY2012	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	7600000	USD
CY2012	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	5000000	USD
CY2014	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.362	pure
CY2013	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.350	pure
CY2012	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.340	pure
CY2014Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	199600000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	272900000	USD
CY2014Q4	us-gaap	Deferred Tax Assets Regulatory Assets And Liabilities DeferredTaxAssetsRegulatoryAssetsAndLiabilities	366700000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Regulatory Assets And Liabilities DeferredTaxAssetsRegulatoryAssetsAndLiabilities	272700000	USD
CY2014Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	632200000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	435200000	USD
CY2013Q4	nu	Deferred Tax Assets Tax Effect Tax Regulatory Liabilities DeferredTaxAssetsTaxEffectTaxRegulatoryLiabilities	16200000	USD
CY2014Q4	nu	Deferred Tax Assets Tax Effect Tax Regulatory Liabilities DeferredTaxAssetsTaxEffectTaxRegulatoryLiabilities	10000000	USD
CY2014Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	198700000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	230600000	USD
CY2014Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	5100000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	24300000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	1559100000	USD
CY2014Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	1647900000	USD
CY2014Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	4215900000	USD
CY2014Q4	nu	Deferred Tax Liabilities Regulatory Assets Other Regulatory Deferrals DeferredTaxLiabilitiesRegulatoryAssetsOtherRegulatoryDeferrals	1277900000	USD
CY2013Q4	nu	Deferred Tax Liabilities Regulatory Assets Other Regulatory Deferrals DeferredTaxLiabilitiesRegulatoryAssetsOtherRegulatoryDeferrals	1146700000	USD
CY2013Q4	nu	Deferred Tax Liabilities Regulatory Assets Tax Effect Tax Regulatory Assets DeferredTaxLiabilitiesRegulatoryAssetsTaxEffectTaxRegulatoryAssets	248200000	USD
CY2014Q4	nu	Deferred Tax Liabilities Regulatory Assets Tax Effect Tax Regulatory Assets DeferredTaxLiabilitiesRegulatoryAssetsTaxEffectTaxRegulatoryAssets	240200000	USD
CY2014Q4	nu	Deferred Tax Liabilities Regulatory Assets Derivative Assets DeferredTaxLiabilitiesRegulatoryAssetsDerivativeAssets	32600000	USD
CY2013Q4	nu	Deferred Tax Liabilities Regulatory Assets Derivative Assets DeferredTaxLiabilitiesRegulatoryAssetsDerivativeAssets	30100000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	157100000	USD
CY2014Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	196300000	USD
CY2014Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	6275700000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	5695200000	USD
CY2014Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1653000000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1583400000	USD
CY2014Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	60500000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	65000000	USD
CY2014Q4	nu	Deferred Tax Liabilities Resulting From Property Tax Accruals And Other DeferredTaxLiabilitiesResultingFromPropertyTaxAccrualsAndOther	109600000	USD
CY2013Q4	nu	Deferred Tax Liabilities Resulting From Property Tax Accruals And Other DeferredTaxLiabilitiesResultingFromPropertyTaxAccrualsAndOther	95100000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	3806500000	USD
CY2014Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	59100000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	158000000	USD
CY2014Q4	nu	Purchase Accounting Deferred Tax Asset PurchaseAccountingDeferredTaxAsset	126200000	USD
CY2013Q4	nu	Purchase Accounting Deferred Tax Asset PurchaseAccountingDeferredTaxAsset	132800000	USD
CY2014Q4	nu	Deferred Tax Liabilities Goodwill Regulatory Asset DeferredTaxLiabilitiesGoodwillRegulatoryAsset	203200000	USD
CY2013Q4	nu	Deferred Tax Liabilities Goodwill Regulatory Asset DeferredTaxLiabilitiesGoodwillRegulatoryAsset	211500000	USD
CY2014Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	46200000	USD
CY2014	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	9300000	USD
CY2011Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	73500000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	10300000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	83100000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	100000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	-800000	USD
CY2013	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	8200000	USD
CY2013	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	-1100000	USD
CY2013Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	38200000	USD
CY2013	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	-49800000	USD
CY2013	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	-2200000	USD
CY2014	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	300000	USD
CY2014	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	-1600000	USD
CY2014	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	400000	USD
CY2013	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	-8600000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	3100000	USD
CY2014Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	1900000	USD
CY2013Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	1500000	USD
CY2013Q4	nu	Tax Adjustments Settlements Total Impact TaxAdjustmentsSettlementsTotalImpact	-13600000	USD
CY2013	us-gaap	Tax Adjustments Settlements And Unusual Provisions TaxAdjustmentsSettlementsAndUnusualProvisions	-8400000	USD
CY2014	us-gaap	Income Tax Examination Description IncomeTaxExaminationDescription	Tax Positions: During 2014, NU did not resolve any of its uncertain tax positions.
CY2013	us-gaap	Income Tax Examination Description IncomeTaxExaminationDescription	During 2013, NU received a Final Determination from the Connecticut Department of Revenue Services (DRS) that concluded its audit of NU's Connecticut income tax returns for the years 2005 through 2008. The DRS Determination resulted in total NU and CL&P after-tax benefits of $13.6 million and $6.9 million, respectively, that included a reduction in NU and CL&P pre-tax interest expense of $8.7 million and $4 million, or $5.2 million and $2.4 million after-tax, respectively. Further, the income tax expense impact resulted in a tax benefit to NU and CL&P of $8.4 million and $4.5 million after-tax, respectively.
CY2014	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	16300000	USD
CY2013	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	14800000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	20100000	USD
CY2014	us-gaap	Other Information Pertaining To Income Taxes OtherInformationPertainingToIncomeTaxes	2014 Federal Legislation: On December 19, 2014, the "Tax Increase Prevention Act of 2014" became law, which extended the accelerated deduction of depreciation to businesses through 2014. This extended stimulus provides NU with cash flow benefits of approximately $200 million (approximately $70 million at CL&P, $50 million at NSTAR Electric, $35 million at PSNH, and $15 million at WMECO) in 2015. 2013 Federal Legislation: On January 2, 2013, the "American Taxpayer Relief Act of 2012" became law, which extended the accelerated deduction of depreciation to businesses through 2013. This extended stimulus provided NU with cash flow benefits of approximately $300 million (approximately $95 million at CL&P, $85 million at NSTAR Electric, $35 million at PSNH, and $50 million at WMECO). On September 13, 2013, the Internal Revenue Service issued final Tangible Property regulations that are meant to simplify, clarify and make more administrable previously issued guidance. NU is in compliance with the new regulations, but continues to evaluate several new potential elections. 2013 Massachusetts: On July 24, 2013, Massachusetts enacted a law that changed the income tax rate applicable to utility companies effective January 1, 2014, from 6.5 percent to 8 percent. The tax law change required NU to remeasure its accumulated deferred income taxes and resulted in NU increasing its deferred tax liability with an offsetting regulatory asset of approximately $61 million at its utility companies ($46.3 million at NSTAR Electric and $9.8 million at WMECO).
CY2014	us-gaap	Significant Change In Unrecognized Tax Benefits Is Reasonably Possible Other Information SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleOtherInformation	NU estimates that during the next twelve months, differences of a non-timing nature could be resolved, resulting in a zero to $2 million decrease in unrecognized tax benefits by NU. These estimated changes are not expected to have a material impact on the earnings of NU. Other companies' impacts are not expected to be material.
CY2012Q4	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	39400000	USD
CY2013	us-gaap	Accrual For Environmental Loss Contingencies Provision For New Losses AccrualForEnvironmentalLossContingenciesProvisionForNewLosses	3500000	USD
CY2013	us-gaap	Accrual For Environmental Loss Contingencies Payments AccrualForEnvironmentalLossContingenciesPayments	7500000	USD
CY2013Q4	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	35400000	USD
CY2014	us-gaap	Accrual For Environmental Loss Contingencies Provision For New Losses AccrualForEnvironmentalLossContingenciesProvisionForNewLosses	12700000	USD
CY2014	us-gaap	Accrual For Environmental Loss Contingencies Payments AccrualForEnvironmentalLossContingenciesPayments	4800000	USD
CY2014Q4	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	43300000	USD
CY2014	nu	Environmental Site Quantity EnvironmentalSiteQuantity	65	pure
CY2013	nu	Environmental Site Quantity EnvironmentalSiteQuantity	68	pure
CY2014	us-gaap	Site Contingency Environmental Remediation Costs Recognized SiteContingencyEnvironmentalRemediationCostsRecognized	CERCLA: Of the total environmental sites, 9 sites (1 for CL&P, 3 for NSTAR Electric and 3 for PSNH) are superfund sites under the federal Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA) and its amendments or state equivalents 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, 2014, a liability of $0.7 million accrued on these sites represents management's best estimate of its potential remediation costs with respect to these superfund sites. Included in the NU number of sites and reserve amounts above are former MGP sites that were operated several decades ago and manufactured gas from coal and other processes, which resulted in certain by-products remaining in the environment that may pose a potential risk to human health and the environment. The reserve balance related to these former MGP sites was $38.8 million and $31.4 million as of December 31, 2014 and 2013, respectively, and relates primarily to the natural gas business segment. The increase in the reserve balance for the MGP sites was due to the completion of the site assessment at three sites. The assessments provided new information related to the extent and nature of the contamination and the costs of required remediation. As of December 31, 2014, for 5 environmental sites (1 for CL&P, 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, 2014, $17.7 million ($1 million for CL&P and $0.3 million for WMECO) 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 with estimated ranges of additional losses from zero to $24 million. As of December 31, 2014, for 15 environmental sites (3 for CL&P, 3 for NSTAR Electric and 2 for PSNH) that are included in the Company’s reserve for environmental costs, management cannot reasonably estimate the exposure to loss in excess of the reserve, or range of loss, as these sites are under investigation and/or there is significant uncertainty as to what remedial actions, if any, the Company may be required to undertake. As of December 31, 2014, $13.4 million ($1.4 million for CL&P, $0.2 million for PSNH) had been accrued as a liability for these sites. As of December 31, 2014, for the remaining 45 environmental sites (12 for CL&P, 10 for NSTAR Electric, 11 for PSNH, and 3 for WMECO) that are included in the Company’s reserve for environmental costs, the $12.2 million accrual ($1.4 million for CL&P, $1.1 million for NSTAR Electric, $5 million for PSNH, and $0.2 million for WMECO) represents management’s best estimate of the liability and no additional loss is anticipated.
CY2014Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Third Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary	421600000	USD
CY2014Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fourth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary	327600000	USD
CY2014Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fifth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFifthAnniversary	290000000	USD
CY2014Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Due After Five Years UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears	2198400000	USD
CY2014Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance Sheet Amount UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount	4521600000	USD
CY2014Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On First Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary	685800000	USD
CY2014Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Second Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary	598200000	USD
CY2014	nu	Supply And Stranded Costs Obligations Incurred SupplyAndStrandedCostsObligationsIncurred	99200000	USD
CY2013	nu	Supply And Stranded Costs Obligations Incurred SupplyAndStrandedCostsObligationsIncurred	141000000	USD
CY2012	nu	Supply And Stranded Costs Obligations Incurred SupplyAndStrandedCostsObligationsIncurred	216800000	USD
CY2014	nu	Peaker Cfd Expense Incurred PeakerCfdExpenseIncurred	18100000	USD
CY2013	nu	Peaker Cfd Expense Incurred PeakerCfdExpenseIncurred	51900000	USD
CY2012	nu	Peaker Cfd Expense Incurred PeakerCfdExpenseIncurred	59300000	USD
CY2014	nu	Natural Gas Procurement Costs Incurred NaturalGasProcurementCostsIncurred	482500000	USD
CY2013	nu	Natural Gas Procurement Costs Incurred NaturalGasProcurementCostsIncurred	349800000	USD
CY2012	nu	Natural Gas Procurement Costs Incurred NaturalGasProcurementCostsIncurred	243100000	USD
CY2012	nu	Fuel Costs Incurred FuelCostsIncurred	105200000	USD
CY2013	nu	Fuel Costs Incurred FuelCostsIncurred	112600000	USD
CY2014	nu	Fuel Costs Incurred FuelCostsIncurred	120500000	USD
CY2014	nu	Transmission Support Commitment Costs Incurred TransmissionSupportCommitmentCostsIncurred	25000000	USD
CY2013	nu	Transmission Support Commitment Costs Incurred TransmissionSupportCommitmentCostsIncurred	24900000	USD
CY2012	nu	Transmission Support Commitment Costs Incurred TransmissionSupportCommitmentCostsIncurred	24800000	USD
CY2014	nu	Renewable Energy Costs Incurred RenewableEnergyCostsIncurred	114400000	USD
CY2013	nu	Renewable Energy Costs Incurred RenewableEnergyCostsIncurred	91300000	USD
CY2012	nu	Renewable Energy Costs Incurred RenewableEnergyCostsIncurred	48700000	USD
CY2014	nu	Myapc Phase One Damages Proceeds To Member Companies MyapcPhaseOneDamagesProceedsToMemberCompanies	On September 17, 2014, in accordance with the MYAPC refund plan, MYAPC returned a portion of the DOE Phase I Damages proceeds to the member companies, including CL&P, NSTAR Electric, PSNH, and WMECO, in the amount of $3.2 million, $1.1 million, $1.4 million and $0.8 million, respectively. These amounts reduced receivables at CL&P, NSTAR Electric, PSNH and WMECO.
CY2014	nu	Refund Obligation To Customers RefundObligationToCustomers	As of December 31, 2014, CL&P's refund obligation to customers of $65.4 million was recorded as an offset to the deferred storm restoration costs regulatory asset, as directed by PURA. NSTAR Electric's, PSNH's and WMECO's refund obligation to customers of $29.1 million, $13.1 million and $18.1 million, respectively, was recorded as a regulatory liability in each company's respective regulatory tracker mechanisms. Refunds to customers for these DOE proceeds began in the third quarter of 2014. For further information, see Note 2, "Regulatory Accounting," to the financial statements.
CY2014	us-gaap	Loss Contingency Managements Assessment And Process LossContingencyManagementsAssessmentAndProcess	E.         FERC Base ROE Complaints E.         FERC Base ROE Complaints Beginning in 2011, several New England state attorneys general, state regulatory commissions, consumer advocates, consumer groups, municipal parties and other parties (the "Complainants") jointly filed three separate complaints at FERC. In the first complaint, filed in 2011, the Complainants alleged that the NETOs' base ROE of 11.14 percent that was utilized since 2006 was unjust and unreasonable, asserted that the rate was excessive due to changes in the capital markets, and sought an order to reduce it prospectively from the date of the final FERC order and for the 15-month period beginning October 1, 2011 to December 31, 2012 (the "first complaint refund period"). In the pursuant second and third complaints, filed in 2012 and 2014, respectively, the Complainants challenged the NETOs' base ROE and sought refunds for the 15-month periods beginning December 27, 2012 and July 31, 2014, respectively. In 2014, the FERC determined that the base ROE should be set at 10.57 percent for the first complaint refund period and that a utility’s total or maximum ROE should not exceed the top of the new zone of reasonableness (7.03 percent to 11.74 percent). The FERC ordered the NETOs to provide refunds to customers for the first complaint refund period and set the new base ROE of 10.57 percent prospectively from October 16, 2014. In late 2014, the NETOs made a compliance filing, and began refunding amounts from the first complaint period, inclusive of incentive ROE adders that exceeded the 11.74 percent as compared to the total company transmission ROE. Complainants have challenged the compliance filing. As a result of the actions taken by the FERC and other developments in this matter, NU recorded reserves in 2013 and 2014 to recognize the potential financial impacts of the first and second complaints. The Company is unable to determine any amount related to the third complaint. The following is a summary of the cumulative pre-tax reserves (excluding interest) established by the Company in 2013 and 2014: As of December 31, 2014, the cumulative reserves above do not reflect refunds totaling $4.8 million at NU, $2.7 million at CL&P, $1 million at NSTAR Electric, $0.5 million at PSNH and $0.6 million at WMECO for the first complaint refund period. The aggregate after-tax net charge to 2014 earnings resulting from the 2014 FERC orders totaled $22.4 million at NU, $12.4 million at CL&P, $4.9 million at NSTAR Electric, $1.7 million at PSNH and $3.4 million at WMECO. In 2013, the aggregate after-tax charge to earnings totaled $14.3 million at NU, $7.7 million at CL&P, $3.4 million at NSTAR Electric, $1.4 million at PSNH and $1.8 million at WMECO. Although management is uncertain on the final outcome on the second and third complaints regarding the base ROE and the incentive ROE adder, management believes the current reserves established are appropriate to reflect probable and reasonably estimable refunds. F.        2014 Comprehensive Settlement Agreement On December 31, 2014, NSTAR Electric, NSTAR Gas and the Massachusetts Attorney General filed a comprehensive settlement agreement with the DPU. The comprehensive settlement agreement included resolution of the outstanding NSTAR Electric CPSL program filings for the periods 2006 through 2011, the NSTAR Electric and NSTAR Gas PAM and energy efficiency-related customer billing adjustments reported in 2012, and the NSTAR Electric energy efficiency program filings regarding LBR for the periods 2008 through 2011. If approved by the DPU, NSTAR Electric and NSTAR Gas will be required to refund a total of $44.7 million to their respective customers, which was included in regulatory liabilities as of December 31, 2014. Upon the DPU's approval, NSTAR Electric will adjust its regulatory liabilities, which it expects will result in a benefit of $23 million in the first quarter of 2015. Management expects a response from the DPU in the first quarter of 2015. G.        Basic Service Bad Debt Adder In accordance with a generic 2005 DPU order, electric utilities in Massachusetts recover the energy-related portion of bad debt costs in their Basic Service rates. In 2007, NSTAR Electric filed its 2006 Basic Service reconciliation with the DPU proposing an adjustment related to the increase of its Basic Service bad debt charge-offs. The DPU issued an order approving the implementation of a revised Basic Service rate but instructed NSTAR Electric to reduce distribution rates by an amount equal to the increase in its Basic Service bad debt charge-offs. This adjustment to NSTAR Electric's distribution rates would eliminate the fully reconciling nature of the Basic Service bad debt adder. In 2010, NSTAR Electric filed an appeal of the DPU's order with the SJC. NSTAR Electric's position was that it had fully removed the collection of energy-related bad debt costs from its distribution rates effective January 1, 2006. Therefore, no further adjustment to distribution rates was warranted. In 2012, the SJC vacated the DPU order and remanded the matter to the DPU for further review. As of December 31, 2014, NSTAR Electric has a total deferred regulatory asset of approximately $33 million of costs associated with energy-related bad debt. On January 7, 2015, the DPU issued an order on remand stating that NSTAR Electric had, in fact, removed energy-related bad debt costs from distribution rates effective January 1, 2006. The DPU order approved NSTAR Electric's 2005 and 2006 reconciliation filings and ordered NSTAR Electric and the Massachusetts Attorney General to collaborate on the submission of a proposal for the reconciliation of energy-related bad debt costs for the open years of 2007 through 2014 by April 7, 2015. Management expects to present a proposal to the Attorney General in the first quarter of 2015 with a decision from the DPU later in 2015. H.        Litigation and Legal Proceedings NU, including CL&P, NSTAR Electric, PSNH and WMECO, are involved in legal, tax and regulatory proceedings regarding matters arising in the ordinary course of business, which involve management's assessment to determine the probability of whether a loss will occur and, if probable, its best estimate of probable loss. The Company records and discloses losses when these losses are probable and reasonably estimable, and discloses matters when losses are probable but not estimable or when losses are reasonably possible. Legal costs related to the defense of loss contingencies are expensed as incurred.
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	17600000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	14600000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	10500000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	8600000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	22500000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	93900000	USD
CY2014Q4	us-gaap	Capital Leases Future Minimum Payments Due Current CapitalLeasesFutureMinimumPaymentsDueCurrent	2400000	USD
CY2014Q4	us-gaap	Capital Leases Future Minimum Payments Due In Two Years CapitalLeasesFutureMinimumPaymentsDueInTwoYears	2200000	USD
CY2014Q4	us-gaap	Capital Leases Future Minimum Payments Due In Three Years CapitalLeasesFutureMinimumPaymentsDueInThreeYears	2100000	USD
CY2014Q4	us-gaap	Capital Leases Future Minimum Payments Due In Four Years CapitalLeasesFutureMinimumPaymentsDueInFourYears	2100000	USD
CY2014Q4	us-gaap	Capital Leases Future Minimum Payments Due In Five Years CapitalLeasesFutureMinimumPaymentsDueInFiveYears	2000000	USD
CY2014Q4	us-gaap	Capital Leases Future Minimum Payments Due Thereafter CapitalLeasesFutureMinimumPaymentsDueThereafter	3500000	USD
CY2014Q4	us-gaap	Capital Leases Future Minimum Payments Due CapitalLeasesFutureMinimumPaymentsDue	14300000	USD
CY2014Q4	us-gaap	Capital Leases Future Minimum Payments Interest Included In Payments CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments	4900000	USD
CY2014Q4	us-gaap	Capital Leases Future Minimum Payments Present Value Of Net Minimum Payments CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments	9400000	USD
CY2012Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-72900000	USD
CY2014	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-33900000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	18500000	USD
CY2013	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-8400000	USD
CY2014	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-5900000	USD
CY2014	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	3500000	USD
CY2014	nu	Pension Serp And Pbop Gain Loss To Be Reclassified Within Twelve Months PensionSerpAndPbopGainLossToBeReclassifiedWithinTwelveMonths	6900000	USD
CY2014	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Before Reclassification Adjustments Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBeforeReclassificationAdjustmentsTax	18700000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Before Reclassification Adjustments Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBeforeReclassificationAdjustmentsTax	11400000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Before Reclassification Adjustments Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBeforeReclassificationAdjustmentsTax	6200000	USD
CY2014	us-gaap	Line Of Credit Facility Dividend Restrictions LineOfCreditFacilityDividendRestrictions	CL&P, NSTAR Electric, 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, NSTAR Electric, 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 and NSTAR Gas. Such state law restrictions do not restrict payment of dividends from retained earnings or net income. Pursuant to the joint revolving credit agreement of NU, CL&P, PSNH, WMECO, Yankee Gas and NSTAR Gas, and the NSTAR Electric revolving credit agreement, each company is required to maintain consolidated total debt to total capitalization ratio of no greater than 65 percent at all times. As of December 31, 2014, all companies were in compliance with such covenant. The Retained Earnings balances subject to these restrictions were $2.4 billion for NU, $1.1 billion for CL&P, $1.5 billion for NSTAR Electric, $486.5 million for PSNH and $178.8 million for WMECO as of December 31, 2014. As of December 31, 2014, NU, CL&P, NSTAR Electric, PSNH, WMECO, Yankee Gas and NSTAR Gas were in compliance with all such provisions of the revolving credit agreements that may restrict the payment of dividends.
CY2014Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	5
CY2013Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	333113492	shares
CY2014Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	333359172	shares
CY2014Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	380000000	shares
CY2014Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	16375835	shares
CY2013Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	17796672	shares
CY2013Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	5
CY2013Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	380000000	shares
CY2014Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	316983337	shares
CY2013Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	315273559	shares
CY2014Q4	us-gaap	Preferred Stock Value Outstanding PreferredStockValueOutstanding	155600000	USD
CY2013Q4	us-gaap	Preferred Stock Value Outstanding PreferredStockValueOutstanding	155600000	USD
CY2014	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	1280666	shares
CY2013	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	899773	shares
CY2012	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	783812	shares
CY2014	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.59
CY2013	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.49
CY2012	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.90
CY2014	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.58
CY2013	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.49
CY2012	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.89
CY2014	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	316136748	shares
CY2014	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	317417414	shares
CY2013	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	315311387	shares
CY2013	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	316211160	shares
CY2012	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	277209819	shares
CY2012	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	277993631	shares
CY2014	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	3643	shares
CY2013	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1575	shares
CY2012	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	4266	shares
CY2012Q2	nu	Number Of Nstar Shares Outstanding NumberOfNstarSharesOutstanding	103696000	shares
CY2012Q2	nu	Exchange Ratio ExchangeRatio	1.312	pure
CY2012Q2	us-gaap	Business Acquisition Equity Interests Issued Or Issuable Number Of Shares Issued BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued	136049000	shares
CY2012Q2	us-gaap	Business Acquisition Share Price BusinessAcquisitionSharePrice	36.79
CY2012Q2	us-gaap	Business Combination Consideration Transferred Other1 BusinessCombinationConsiderationTransferredOther1	33000000	USD
CY2012Q2	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	5038000000	USD
CY2012Q2	us-gaap	Business Acquisition Percentage Of Voting Interests Acquired BusinessAcquisitionPercentageOfVotingInterestsAcquired	1.00	pure
CY2012Q2	nu	Business Acquisition Number Of Shares Awarded Vested Immediately Prior To Merger BusinessAcquisitionNumberOfSharesAwardedVestedImmediatelyPriorToMerger	109000	shares
CY2012Q2	us-gaap	Business Combination Consideration Transferred Equity Interests Issued And Issuable BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable	5005000000	USD
CY2012Q2	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	3232000000	USD
CY2012	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	7004000000	USD
CY2012	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	630000000	USD
CY2012	us-gaap	Business Acquisition Pro Forma Earnings Per Share Diluted BusinessAcquisitionProFormaEarningsPerShareDiluted	1.99
CY2012	us-gaap	Business Acquisition Pro Forma Earnings Per Share Basic BusinessAcquisitionProFormaEarningsPerShareBasic	2.00
CY2012	nu	Business Combination After Tax Transaction Costs BusinessCombinationAfterTaxTransactionCosts	32000000	USD
CY2012	nu	After Tax Settlement Costs Incurred AfterTaxSettlementCostsIncurred	60000000	USD
CY2012	nu	After Tax Costs Transaction And Other Non Recurring Costs Excluded From Pro Forma Net Income AfterTaxCostsTransactionAndOtherNonRecurringCostsExcludedFromProFormaNetIncome	92000000	USD
CY2014Q2	us-gaap	Revenues Revenues	1677600000	USD
CY2012	nu	Business Acquisition Description Of Settlement Agreements BusinessAcquisitionDescriptionOfSettlementAgreements	Regulatory Approvals: On February 15, 2012, NU and NSTAR reached comprehensive merger settlement agreements with the Massachusetts Attorney General and the DOER. The Attorney General settlement agreement covered a variety of rate-making and rate design issues, including a base distribution rate freeze through 2015 for NSTAR Electric, NSTAR Gas and WMECO and $15 million, $3 million and $3 million in the form of rate credits to their respective customers. On April 4, 2012, the DPU approved the settlement agreements and the merger of NU and NSTAR. On March 13, 2012, NU and NSTAR reached a comprehensive merger settlement agreement with both the Connecticut Attorney General and the Connecticut Office of Consumer Counsel. The settlement agreement covered a variety of matters, including a $25 million rate credit to CL&P customers, a CL&P base distribution rate freeze until December 1, 2014, and the establishment of a $15 million fund for energy efficiency and other initiatives to be disbursed at the direction of the DEEP. In the agreement, CL&P agreed to forego rate recovery of $40 million of the deferred storm restoration costs associated with restoration activities following Tropical Storm Irene and the October 2011 snowstorm. On April 2, 2012, the PURA approved the settlement agreement and the merger of NU and NSTAR.
CY2012	nu	Customer Rate Credits For Business Combination CustomerRateCreditsForBusinessCombination	46000000	USD
CY2012	nu	Storm Cost Deferral Reduction StormCostDeferralReduction	40000000	USD
CY2012	nu	Establishment Of Energy Efficiency Fund EstablishmentOfEnergyEfficiencyFund	15000000	USD
CY2012	nu	Total Pre Tax Settlement Agreement Impacts TotalPreTaxSettlementAgreementImpacts	101000000	USD
CY2012	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	3200000000	USD
CY2014Q3	us-gaap	Revenues Revenues	1892500000	USD
CY2014Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	440900000	USD
CY2014Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	294000000	USD
CY2014Q2	us-gaap	Net Income Loss NetIncomeLoss	129200000	USD
CY2014Q3	us-gaap	Net Income Loss NetIncomeLoss	236500000	USD
CY2014Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	234600000	USD
CY2014Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	127400000	USD
CY2013Q2	us-gaap	Revenues Revenues	1635900000	USD
CY2013Q3	us-gaap	Revenues Revenues	1892600000	USD
CY2013Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	399300000	USD
CY2013Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	350600000	USD
CY2014	dei	Entity Registrant Name EntityRegistrantName	NORTHEAST UTILITIES
CY2014	dei	Document Type DocumentType	10-K
CY2014	dei	Document Period End Date DocumentPeriodEndDate	2014-12-31
CY2014	dei	Entity Central Index Key EntityCentralIndexKey	0000072741
CY2013Q2	us-gaap	Net Income Loss NetIncomeLoss	173100000	USD
CY2013Q3	us-gaap	Net Income Loss NetIncomeLoss	211400000	USD
CY2013Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	209500000	USD
CY2013Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	171000000	USD
CY2014Q1	us-gaap	Revenues Revenues	2290600000	USD
CY2014Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	467700000	USD
CY2014Q1	us-gaap	Net Income Loss NetIncomeLoss	237800000	USD
CY2013Q1	us-gaap	Revenues Revenues	1995000000	USD
CY2013Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	418900000	USD
CY2013Q1	us-gaap	Net Income Loss NetIncomeLoss	230000000	USD
CY2013Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	228100000	USD
CY2014Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	236000000	USD
CY2014Q4	us-gaap	Revenues Revenues	1881200000	USD
CY2014Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	430200000	USD
CY2014Q4	us-gaap	Net Income Loss NetIncomeLoss	223600000	USD
CY2014Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	221500000	USD
CY2013Q4	us-gaap	Revenues Revenues	1777700000	USD
CY2013Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	360600000	USD
CY2013Q4	us-gaap	Net Income Loss NetIncomeLoss	179200000	USD
CY2013Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	177400000	USD
CY2014Q1	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.75
CY2014Q2	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.40
CY2014Q3	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.74
CY2014Q4	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.69
CY2013Q4	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.56
CY2013Q3	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.66
CY2013Q2	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.54
CY2013Q1	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	0.72
CY2013	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	55465000	USD
CY2012	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	36275000	USD
CY2013	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	87507000	USD
CY2012	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	80462000	USD
CY2011Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	115689000	USD
CY2012Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	165549000	USD
CY2013	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	37744000	USD
CY2012	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	34761000	USD
CY2013Q4	nu	Impact Related To Nstar Merger ImpactRelatedToNstarMerger	0	USD
CY2012Q4	nu	Uncollectible Hardship Accounts Receivable Reserves UncollectibleHardshipAccountsReceivableReserves		USD
CY2012Q4	nu	Impact Related To Nstar Merger ImpactRelatedToNstarMerger	59286000	USD
CY2013Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	171251000	USD
CY2014	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	55657000	USD
CY2014	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	51227000	USD
CY2014Q4	nu	Impact Related To Nstar Merger ImpactRelatedToNstarMerger	0	USD
CY2014	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	102818000	USD
CY2014Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	175317000	USD
CY2014	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2015Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	317203765	shares
CY2014Q2	dei	Entity Public Float EntityPublicFloat	14947688864	USD
CY2014	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2014	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2014	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2014	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2014	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2014
CY2014	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2014	dei	Amendment Flag AmendmentFlag	false
CY2014	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	22000000	USD

Files In Submission

Name	View Source	Status
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2014 Q4 Form 10-K Financial Statement

#000007274115000013 Filed on February 25, 2015

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Cashflow Statement

Facts In Submission

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2014 Q4 Form 10-K Financial Statement

#000007274115000013 Filed on February 25, 2015

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

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