$LNT
ALLIANT ENERGY CORP Stock $lnt

$lnt Overview Financials Valuation SEC Filings Company Website

2014 Q4 Form 10-K Financial Statement

#000035254115000005 Filed on February 25, 2015

Income Statement

Concept	2014 Q4	2013 Q4	2013 Q3
Revenue	$804.1M	$832.6M	$866.6M
YoY Change	-3.42%	10.88%	-2.37%
Cost Of Revenue	$99.30M	$144.7M	$72.90M
YoY Change	-31.38%	10.12%	-28.32%
Gross Profit	$704.8M	$687.9M	$793.7M
YoY Change	2.46%	11.04%	0.99%
Gross Profit Margin	87.65%	82.62%	91.59%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$99.70M	$93.50M	$92.10M
YoY Change	6.63%	10.0%	10.17%
% of Gross Profit	14.15%	13.59%	11.6%
Operating Expenses	$613.5M	$579.3M	$592.3M
YoY Change	5.9%	11.86%	3.51%
Operating Profit	$91.30M	$108.6M	$201.4M
YoY Change	-15.93%	6.89%	-5.76%
Interest Expense	-$30.50M	-$25.80M	$42.50M
YoY Change	18.22%	23.44%	10.97%
% of Operating Profit	-33.41%	-23.76%	21.1%
Other Income/Expense, Net			-$22.30M
YoY Change			4.21%
Pretax Income	$60.80M	$82.80M	$179.1M
YoY Change	-26.57%	2.6%	-6.86%
Income Tax	-$1.900M	$13.70M	$17.60M
% Of Pretax Income	-3.13%	16.55%	9.83%
Net Earnings	$62.50M	$68.10M	$160.2M
YoY Change	-8.22%	-5.81%	3.56%
Net Earnings / Revenue	7.77%	8.18%	18.49%
Basic Earnings Per Share
Diluted Earnings Per Share	$0.54	$0.59	$1.42
COMMON SHARES
Basic Shares Outstanding			110.8M shares
Diluted Shares Outstanding			110.8M shares

Balance Sheet

Concept	2014 Q4	2013 Q4	2013 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$57.00M	$10.00M	$18.00M
YoY Change	470.0%	-52.38%	-56.1%
Cash & Equivalents	$56.90M	$9.800M	$17.70M
Short-Term Investments
Other Short-Term Assets	$116.9M	$125.7M	$119.0M
YoY Change	-7.0%	40.6%	185.37%
Inventory	$224.0M	$212.0M	$221.0M
Prepaid Expenses
Receivables	$427.3M	$473.3M	$78.10M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$1.043B	$1.011B	$880.1M
YoY Change	3.15%	1.7%	-14.44%
LONG-TERM ASSETS
Property, Plant & Equipment	$8.938B	$8.327B	$8.141B
YoY Change	7.35%	6.23%	10.25%
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments	$296.6M	$281.4M	$325.0M
YoY Change	5.4%	5.55%	3.5%
Other Assets	$21.50M	$85.80M	$99.10M
YoY Change	-74.94%	-18.52%	1.02%
Total Long-Term Assets	$11.02B	$10.08B	$10.10B
YoY Change	9.32%	2.96%	9.53%
TOTAL ASSETS
Total Short-Term Assets	$1.043B	$1.011B	$880.1M
Total Long-Term Assets	$11.02B	$10.08B	$10.10B
Total Assets	$12.06B	$11.09B	$10.98B
YoY Change	8.75%	2.85%	7.12%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$427.9M	$365.0M	$368.7M
YoY Change	17.23%	7.57%	-11.79%
Accrued Expenses		$51.00M
YoY Change		6.25%
Deferred Revenue
YoY Change
Short-Term Debt	$141.0M	$279.0M	$237.0M
YoY Change	-49.46%	27.98%	238.57%
Long-Term Debt Due	$183.0M	$358.5M	$48.40M
YoY Change	-48.95%	23800.0%	3357.14%
Total Short-Term Liabilities	$1.215B	$1.433B	$1.053B
YoY Change	-15.25%	40.52%	11.35%
LONG-TERM LIABILITIES
Long-Term Debt	$3.584B	$2.978B	$3.105B
YoY Change	20.37%	-5.06%	9.78%
Other Long-Term Liabilities	$260.1M	$273.9M	$271.9M
YoY Change	-5.04%	4.34%	1.04%
Total Long-Term Liabilities	$3.844B	$3.252B	$3.377B
YoY Change	18.23%	-4.34%	9.02%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.215B	$1.433B	$1.053B
Total Long-Term Liabilities	$3.844B	$3.252B	$3.377B
Total Liabilities	$5.059B	$4.685B	$4.430B
YoY Change	7.99%	6.02%	9.57%
SHAREHOLDERS EQUITY
Retained Earnings	$1.938B	$1.781B	$1.767B
YoY Change	8.83%	9.2%	9.63%
Common Stock	$1.510B	$1.509B	$1.508B
YoY Change	0.09%	-0.22%	-0.34%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$3.439B	$3.281B	$3.267B
YoY Change
Total Liabilities & Shareholders Equity	$12.06B	$11.11B	$10.98B
YoY Change	8.56%	3.03%	7.12%

Cashflow Statement

Concept	2014 Q4	2013 Q4	2013 Q3
OPERATING ACTIVITIES
Net Income	$62.50M	$68.10M	$160.2M
YoY Change	-8.22%	-5.81%	3.56%
Depreciation, Depletion And Amortization	$99.70M	$93.50M	$92.10M
YoY Change	6.63%	10.0%	10.17%
Cash From Operating Activities	$127.7M	$87.90M	$219.8M
YoY Change	45.28%	-63.5%	-15.82%
INVESTING ACTIVITIES
Capital Expenditures	-$251.5M	-$207.2M	-$182.9M
YoY Change	21.38%	-66.19%	10.58%
Acquisitions
YoY Change
Other Investing Activities	-$25.80M	-$34.30M	-$8.100M
YoY Change	-24.78%	37.2%	-73.44%
Cash From Investing Activities	-$277.3M	-$241.5M	-$191.0M
YoY Change	14.82%	-62.14%	-2.5%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	195.5M	145.7M	-22.60M
YoY Change	34.18%	-61.36%	-58.83%
NET CHANGE
Cash From Operating Activities	127.7M	87.90M	219.8M
Cash From Investing Activities	-277.3M	-241.5M	-191.0M
Cash From Financing Activities	195.5M	145.7M	-22.60M
Net Change In Cash	45.90M	-7.900M	6.200M
YoY Change	-681.01%	-60.3%	-39.81%
FREE CASH FLOW
Cash From Operating Activities	$127.7M	$87.90M	$219.8M
Capital Expenditures	-$251.5M	-$207.2M	-$182.9M
Free Cash Flow	$379.2M	$295.1M	$402.7M
YoY Change	28.5%	-65.43%	-5.58%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2014	dei	Amendment Flag AmendmentFlag	false
CY2014	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2014	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2014
CY2014	dei	Document Period End Date DocumentPeriodEndDate	2014-12-31
CY2014	dei	Document Type DocumentType	10-K
CY2014	dei	Entity Central Index Key EntityCentralIndexKey	0000352541
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CY2014	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2014	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2014Q2	dei	Entity Public Float EntityPublicFloat	6700000000	USD
CY2014	dei	Entity Registrant Name EntityRegistrantName	ALLIANT ENERGY CORP
CY2014	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2014	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
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CY2014Q4	lnt	Accumulated Depreciation On Property Plant And Equipment Non Regulated Business Line1 AccumulatedDepreciationOnPropertyPlantAndEquipmentNonRegulatedBusinessLine1	49500000	USD
CY2013Q4	lnt	Accumulated Depreciation On Property Plant And Equipment Non Regulated Business Line2 AccumulatedDepreciationOnPropertyPlantAndEquipmentNonRegulatedBusinessLine2	214200000	USD
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CY2012	lnt	Cost Of Gas Sold CostOfGasSold	217200000	USD
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CY2014	lnt	Cost Of Gas Sold CostOfGasSold	327800000	USD
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CY2013	lnt	Cost Purchased Electric Capacity CostPurchasedElectricCapacity	216800000	USD
CY2014	lnt	Cost Purchased Electric Capacity CostPurchasedElectricCapacity	25100000	USD
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CY2013	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	5600000	USD
CY2014	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	0	USD
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CY2013Q4	us-gaap	Assets Assets	11112400000	USD
CY2014Q4	us-gaap	Assets Assets	12085900000	USD
CY2013Q4	us-gaap	Assets Current AssetsCurrent	1011200000	USD
CY2014Q4	us-gaap	Assets Current AssetsCurrent	1043100000	USD
CY2014Q4	us-gaap	Assets Of Disposal Group Including Discontinued Operation AssetsOfDisposalGroupIncludingDiscontinuedOperation	19100000	USD
CY2014Q4	us-gaap	Assets Of Disposal Group Including Discontinued Operation Current AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent	1100000	USD
CY2012	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	105300000	USD
CY2013	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	103800000	USD
CY2014	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	160300000	USD
CY2011Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	11400000	USD
CY2012Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	21200000	USD
CY2013Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	9800000	USD
CY2014Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	56900000	USD
CY2012	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	9800000	USD
CY2013	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-11400000	USD
CY2014	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	47100000	USD
CY2013Q4	us-gaap	Cash Surrender Value Of Life Insurance CashSurrenderValueOfLifeInsurance	46500000	USD
CY2014Q4	us-gaap	Cash Surrender Value Of Life Insurance CashSurrenderValueOfLifeInsurance	47000000	USD
CY2014Q4	us-gaap	Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1 ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1	110.00
CY2013Q4	us-gaap	Commercial Paper CommercialPaper	279400000	USD
CY2014Q4	us-gaap	Commercial Paper CommercialPaper	141300000	USD
CY2013Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2014Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2012	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.80
CY2013	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.88
CY2014	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.04
CY2013Q4	us-gaap	Common Stock Held In Trust CommonStockHeldInTrust	8000000	USD
CY2014Q4	us-gaap	Common Stock Held In Trust CommonStockHeldInTrust	8900000	USD
CY2013Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2014Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2013Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	240000000	shares
CY2014Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	240000000	shares
CY2011Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	111018821	shares
CY2012Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	110987400	shares
CY2013Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	110943669	shares
CY2014Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	110935680	shares
CY2013Q4	us-gaap	Common Stock Value CommonStockValue	1100000	USD
CY2014Q4	us-gaap	Common Stock Value CommonStockValue	1100000	USD
CY2012	us-gaap	Concentration Risk Percentage1 ConcentrationRiskPercentage1	1.00
CY2013	us-gaap	Concentration Risk Percentage1 ConcentrationRiskPercentage1	1.00
CY2014	us-gaap	Concentration Risk Percentage1 ConcentrationRiskPercentage1	1.00
CY2012	us-gaap	Cost Of Transmission CostOfTransmission	341300000	USD
CY2013	us-gaap	Cost Of Transmission CostOfTransmission	418300000	USD
CY2014	us-gaap	Cost Of Transmission CostOfTransmission	447500000	USD
CY2012	us-gaap	Costs And Expenses CostsAndExpenses	2574800000	USD
CY2013	us-gaap	Costs And Expenses CostsAndExpenses	2742900000	USD
CY2014	us-gaap	Costs And Expenses CostsAndExpenses	2806700000	USD
CY2013Q4	us-gaap	Costs In Excess Of Billings On Uncompleted Contracts Or Programs Expected To Be Collected Within One Year CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear	92300000	USD
CY2014Q4	us-gaap	Costs In Excess Of Billings On Uncompleted Contracts Or Programs Expected To Be Collected Within One Year CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear	85400000	USD
CY2012	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-29300000	USD
CY2013	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	4400000	USD
CY2014	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	36600000	USD
CY2012	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	11600000	USD
CY2013	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-3600000	USD
CY2014	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	9300000	USD
CY2013Q4	us-gaap	Debt Instrument Fair Value DebtInstrumentFairValue	3712300000	USD
CY2014Q4	us-gaap	Debt Instrument Fair Value DebtInstrumentFairValue	4418200000	USD
CY2013Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	-12100000	USD
CY2014Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	-13100000	USD
CY2013Q4	us-gaap	Deferred Credits And Other Liabilities DeferredCreditsAndOtherLiabilities	3218100000	USD
CY2014Q4	us-gaap	Deferred Credits And Other Liabilities DeferredCreditsAndOtherLiabilities	3624000000	USD
CY2012	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	157800000	USD
CY2013	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	123900000	USD
CY2014	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	83500000	USD
CY2012	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	143300000	USD
CY2013	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	108300000	USD
CY2014	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	55200000	USD
CY2012	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	23900000	USD
CY2013	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	15600000	USD
CY2014	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	4600000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Net Current DeferredTaxAssetsNetCurrent	136700000	USD
CY2014Q4	us-gaap	Deferred Tax Assets Net Current DeferredTaxAssetsNetCurrent	150100000	USD
CY2014Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	580000000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	1976000000	USD
CY2014Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	2171000000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	2112700000	USD
CY2014Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	2321100000	USD
CY2014Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Five Fiscal Years Thereafter DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter	480100000	USD
CY2014Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Next Twelve Months DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths	84300000	USD
CY2014Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Year Five DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive	90600000	USD
CY2014Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Year Four DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour	89800000	USD
CY2014Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Year Three DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree	86000000	USD
CY2014Q4	us-gaap	Defined Benefit Plan Expected Future Benefit Payments Year Two DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo	88300000	USD
CY2012	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	18500000	USD
CY2013	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	19200000	USD
CY2014	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	22500000	USD
CY2012	us-gaap	Depreciation And Amortization DepreciationAndAmortization	332400000	USD
CY2013	us-gaap	Depreciation And Amortization DepreciationAndAmortization	370900000	USD
CY2014	us-gaap	Depreciation And Amortization DepreciationAndAmortization	388100000	USD
CY2013Q4	us-gaap	Derivative Assets DerivativeAssets	23500000	USD
CY2014Q4	us-gaap	Derivative Assets DerivativeAssets	33000000	USD
CY2013Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	26700000	USD
CY2014Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	38600000	USD
CY2013Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	20800000	USD
CY2014Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	37600000	USD
CY2013Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	17600000	USD
CY2014Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	32000000	USD
CY2013Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	20800000	USD
CY2014Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	37600000	USD
CY2012	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-8500000	USD
CY2013	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-9000000	USD
CY2014	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-3700000	USD
CY2012	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-3400000	USD
CY2013	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-3100000	USD
CY2014	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-1300000	USD
CY2012	us-gaap	Disposal Group Including Discontinued Operation Operating Expense DisposalGroupIncludingDiscontinuedOperationOperatingExpense	297000000	USD
CY2013	us-gaap	Disposal Group Including Discontinued Operation Operating Expense DisposalGroupIncludingDiscontinuedOperationOperatingExpense	9900000	USD
CY2014	us-gaap	Disposal Group Including Discontinued Operation Operating Expense DisposalGroupIncludingDiscontinuedOperationOperatingExpense	3700000	USD
CY2014Q4	us-gaap	Disposal Group Including Discontinued Operation Other Assets DisposalGroupIncludingDiscontinuedOperationOtherAssets	7000000	USD
CY2014Q4	us-gaap	Disposal Group Including Discontinued Operation Property Plant And Equipment DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipment	11000000	USD
CY2012	us-gaap	Disposal Group Including Discontinued Operation Revenue DisposalGroupIncludingDiscontinuedOperationRevenue	289200000	USD
CY2013	us-gaap	Disposal Group Including Discontinued Operation Revenue DisposalGroupIncludingDiscontinuedOperationRevenue	900000	USD
CY2014	us-gaap	Disposal Group Including Discontinued Operation Revenue DisposalGroupIncludingDiscontinuedOperationRevenue	0	USD
CY2012	us-gaap	Dividends Common Stock DividendsCommonStock	199300000	USD
CY2013	us-gaap	Dividends Common Stock DividendsCommonStock	208300000	USD
CY2014	us-gaap	Dividends Common Stock DividendsCommonStock	225800000	USD
CY2012	us-gaap	Dividends Preferred Stock DividendsPreferredStock	15900000	USD
CY2013	us-gaap	Dividends Preferred Stock DividendsPreferredStock	17900000	USD
CY2014	us-gaap	Dividends Preferred Stock DividendsPreferredStock	10200000	USD
CY2012	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	2.89
CY2013	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	3.23
CY2014	us-gaap	Earnings Per Share Basic And Diluted EarningsPerShareBasicAndDiluted	3.46
CY2013Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.63
CY2013Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.59
CY2013Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.42
CY2013Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.59
CY2014Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.97
CY2014Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.56
CY2014Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.38
CY2014Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.54
CY2012	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.208
CY2013	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.124
CY2014	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.101
CY2012	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2013	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2014	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Deductions Qualified Production Activities EffectiveIncomeTaxRateReconciliationDeductionsQualifiedProductionActivities	0.058
CY2013	us-gaap	Effective Income Tax Rate Reconciliation Deductions Qualified Production Activities EffectiveIncomeTaxRateReconciliationDeductionsQualifiedProductionActivities	0.071
CY2014	us-gaap	Effective Income Tax Rate Reconciliation Deductions Qualified Production Activities EffectiveIncomeTaxRateReconciliationDeductionsQualifiedProductionActivities	0.071
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.014
CY2013	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.018
CY2014	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.015
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	0.000
CY2013	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	-0.013
CY2014	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	-0.013
CY2012	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.057
CY2013	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.057
CY2014	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.054
CY2012	us-gaap	Electric Domestic Regulated Revenue ElectricDomesticRegulatedRevenue	2589300000	USD
CY2013	us-gaap	Electric Domestic Regulated Revenue ElectricDomesticRegulatedRevenue	2689000000	USD
CY2014	us-gaap	Electric Domestic Regulated Revenue ElectricDomesticRegulatedRevenue	2713600000	USD
CY2014Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	6500000	USD
CY2012	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	2800000	USD
CY2013	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4800000	USD
CY2014	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	6200000	USD
CY2013Q4	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	38600000	USD
CY2014Q4	us-gaap	Energy Related Inventory Gas Stored Underground EnergyRelatedInventoryGasStoredUnderground	67100000	USD
CY2013Q4	us-gaap	Energy Related Inventory Other Fossil Fuel EnergyRelatedInventoryOtherFossilFuel	103600000	USD
CY2014Q4	us-gaap	Energy Related Inventory Other Fossil Fuel EnergyRelatedInventoryOtherFossilFuel	83800000	USD
CY2012	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	34200000	USD
CY2013	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	35400000	USD
CY2014	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	36400000	USD
CY2013Q4	us-gaap	Equity Method Investment Summarized Financial Information Current Assets EquityMethodInvestmentSummarizedFinancialInformationCurrentAssets	86000000	USD
CY2014Q4	us-gaap	Equity Method Investment Summarized Financial Information Current Assets EquityMethodInvestmentSummarizedFinancialInformationCurrentAssets	72000000	USD
CY2013Q4	us-gaap	Equity Method Investment Summarized Financial Information Current Liabilities EquityMethodInvestmentSummarizedFinancialInformationCurrentLiabilities	383000000	USD
CY2014Q4	us-gaap	Equity Method Investment Summarized Financial Information Current Liabilities EquityMethodInvestmentSummarizedFinancialInformationCurrentLiabilities	315000000	USD
CY2012	us-gaap	Equity Method Investment Summarized Financial Information Gross Profit Loss EquityMethodInvestmentSummarizedFinancialInformationGrossProfitLoss	326000000	USD
CY2013	us-gaap	Equity Method Investment Summarized Financial Information Gross Profit Loss EquityMethodInvestmentSummarizedFinancialInformationGrossProfitLoss	334000000	USD
CY2014	us-gaap	Equity Method Investment Summarized Financial Information Gross Profit Loss EquityMethodInvestmentSummarizedFinancialInformationGrossProfitLoss	330000000	USD
CY2012	us-gaap	Equity Method Investment Summarized Financial Information Net Income Loss EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss	234000000	USD
CY2013	us-gaap	Equity Method Investment Summarized Financial Information Net Income Loss EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss	248000000	USD
CY2014	us-gaap	Equity Method Investment Summarized Financial Information Net Income Loss EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss	240000000	USD
CY2013Q4	us-gaap	Equity Method Investment Summarized Financial Information Noncurrent Assets EquityMethodInvestmentSummarizedFinancialInformationNoncurrentAssets	3553000000	USD
CY2014Q4	us-gaap	Equity Method Investment Summarized Financial Information Noncurrent Assets EquityMethodInvestmentSummarizedFinancialInformationNoncurrentAssets	3773000000	USD
CY2013Q4	us-gaap	Equity Method Investment Summarized Financial Information Noncurrent Liabilities EquityMethodInvestmentSummarizedFinancialInformationNoncurrentLiabilities	1682000000	USD
CY2014Q4	us-gaap	Equity Method Investment Summarized Financial Information Noncurrent Liabilities EquityMethodInvestmentSummarizedFinancialInformationNoncurrentLiabilities	1871000000	USD
CY2012	us-gaap	Equity Method Investment Summarized Financial Information Revenue EquityMethodInvestmentSummarizedFinancialInformationRevenue	611000000	USD
CY2013	us-gaap	Equity Method Investment Summarized Financial Information Revenue EquityMethodInvestmentSummarizedFinancialInformationRevenue	634000000	USD
CY2014	us-gaap	Equity Method Investment Summarized Financial Information Revenue EquityMethodInvestmentSummarizedFinancialInformationRevenue	643000000	USD
CY2012Q4	us-gaap	Equity Method Investments EquityMethodInvestments	266600000	USD
CY2013Q4	us-gaap	Equity Method Investments EquityMethodInvestments	281400000	USD
CY2014Q4	us-gaap	Equity Method Investments EquityMethodInvestments	296600000	USD
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	-0.04
CY2013	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	-0.06
CY2014	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	-0.02
CY2013Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.03
CY2012	us-gaap	Gas Domestic Regulated Revenue GasDomesticRegulatedRevenue	396300000	USD
CY2013	us-gaap	Gas Domestic Regulated Revenue GasDomesticRegulatedRevenue	464800000	USD
CY2014	us-gaap	Gas Domestic Regulated Revenue GasDomesticRegulatedRevenue	517500000	USD
CY2012	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	324900000	USD
CY2013Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	72900000	USD
CY2013Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	65900000	USD
CY2013Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	158900000	USD
CY2013Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	66500000	USD
CY2013	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	364200000	USD
CY2014Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	108000000	USD
CY2014Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	62100000	USD
CY2014Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	155200000	USD
CY2014Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	60200000	USD
CY2014	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	385500000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	430200000	USD
CY2013	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	436000000	USD
CY2014	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	440000000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	340800000	USD
CY2013	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	382100000	USD
CY2014	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	395700000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	2.93
CY2013	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	3.29
CY2014	us-gaap	Income Loss From Continuing Operations Per Basic And Diluted Share IncomeLossFromContinuingOperationsPerBasicAndDilutedShare	3.48
CY2013Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.66
CY2013Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.59
CY2013Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.43
CY2013Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.60
CY2014Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.97
CY2014Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.56
CY2014Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.40
CY2014Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.54
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-5100000	USD
CY2013	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-5900000	USD
CY2014	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-2400000	USD
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-5100000	USD
CY2013Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-3000000	USD
CY2013Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-600000	USD
CY2013Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1300000	USD
CY2013Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1000000	USD
CY2013	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-5900000	USD
CY2014Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	USD
CY2014Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-300000	USD
CY2014Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1900000	USD
CY2014Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-200000	USD
CY2014	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-2400000	USD
CY2013Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.00
CY2013Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.01
CY2013Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.01
CY2014Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.00
CY2014Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.00
CY2014Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.02
CY2014Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.00
CY2012	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	41300000	USD
CY2013	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	43700000	USD
CY2014	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	40400000	USD
CY2012	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	89400000	USD
CY2013	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	53900000	USD
CY2014	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	44300000	USD
CY2012	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-20300000	USD
CY2013	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-9600000	USD
CY2014	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-5300000	USD
CY2012	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-61300000	USD
CY2013	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	49200000	USD
CY2014	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-48700000	USD
CY2012	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	14100000	USD
CY2013	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	20300000	USD
CY2014	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	23100000	USD
CY2012	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-69700000	USD
CY2013	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-101900000	USD
CY2014	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-138400000	USD
CY2012	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	15900000	USD
CY2013	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-23700000	USD
CY2014	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-59700000	USD
CY2012	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	10000000	USD
CY2013	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	101000000	USD
CY2014	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	7000000	USD
CY2012	us-gaap	Increase Decrease In Other Regulatory Assets IncreaseDecreaseInOtherRegulatoryAssets	178100000	USD
CY2013	us-gaap	Increase Decrease In Other Regulatory Assets IncreaseDecreaseInOtherRegulatoryAssets	-140500000	USD
CY2014	us-gaap	Increase Decrease In Other Regulatory Assets IncreaseDecreaseInOtherRegulatoryAssets	439800000	USD
CY2012	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	51300000	USD
CY2013	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	-157400000	USD
CY2014	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	215100000	USD
CY2012	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	16400000	USD
CY2013	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	-90800000	USD
CY2014	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	10800000	USD
CY2012	us-gaap	Interest Expense InterestExpense	156700000	USD
CY2013	us-gaap	Interest Expense InterestExpense	172800000	USD
CY2014	us-gaap	Interest Expense InterestExpense	180600000	USD
CY2012	us-gaap	Interest Paid Net InterestPaidNet	155200000	USD
CY2013	us-gaap	Interest Paid Net InterestPaidNet	171700000	USD
CY2014	us-gaap	Interest Paid Net InterestPaidNet	180800000	USD
CY2013Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	69600000	USD
CY2014Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	72900000	USD
CY2012	us-gaap	Investment Tax Credit InvestmentTaxCredit	-1700000	USD
CY2013	us-gaap	Investment Tax Credit InvestmentTaxCredit	-1600000	USD
CY2014	us-gaap	Investment Tax Credit InvestmentTaxCredit	-1600000	USD
CY2014Q4	us-gaap	Jointly Owned Utility Plant Gross Ownership Amount Of Plant In Service JointlyOwnedUtilityPlantGrossOwnershipAmountOfPlantInService	1488100000	USD
CY2014Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Construction Work In Progress JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress	22400000	USD
CY2014Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Plant Accumulated Depreciation JointlyOwnedUtilityPlantOwnershipAmountOfPlantAccumulatedDepreciation	486800000	USD
CY2013Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	11112400000	USD
CY2014Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	12085900000	USD
CY2013Q4	us-gaap	Liabilities Current LiabilitiesCurrent	1433300000	USD
CY2014Q4	us-gaap	Liabilities Current LiabilitiesCurrent	1214700000	USD
CY2014Q4	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation	8100000	USD
CY2014Q4	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation Current LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent	1000000	USD
CY2014Q4	us-gaap	Liabilities Of Disposal Group Including Discontinued Operation Noncurrent LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationNoncurrent	7100000	USD
CY2014Q4	us-gaap	Line Of Credit Facility Current Borrowing Capacity LineOfCreditFacilityCurrentBorrowingCapacity	1000000000	USD
CY2013Q4	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	720600000	USD
CY2014Q4	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	858700000	USD
CY2013Q4	us-gaap	Long Term Debt LongTermDebt	3348400000	USD
CY2014Q4	us-gaap	Long Term Debt LongTermDebt	3802800000	USD
CY2013Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	358500000	USD
CY2014Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	183000000	USD
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	183000000	USD
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	256000000	USD
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	356000000	USD
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	5000000	USD
CY2014Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	313000000	USD
CY2013Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2977800000	USD
CY2014Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	3606700000	USD
CY2013Q4	us-gaap	Long Term Investments LongTermInvestments	329600000	USD
CY2014Q4	us-gaap	Long Term Investments LongTermInvestments	344900000	USD
CY2014	us-gaap	Long Term Purchase Commitment Amount LongTermPurchaseCommitmentAmount	2360000000	USD
CY2013Q4	us-gaap	Minority Interest Preferred Stock Amount MinorityInterestPreferredStockAmount	200000000	USD
CY2014Q4	us-gaap	Minority Interest Preferred Stock Amount MinorityInterestPreferredStockAmount	200000000	USD
CY2012	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	324200000	USD
CY2013	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	12300000	USD
CY2014	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	73200000	USD
CY2012	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1155500000	USD
CY2013	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-754700000	USD
CY2014	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-917700000	USD
CY2012	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	841100000	USD
CY2013	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	731000000	USD
CY2014	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	891600000	USD
CY2012	us-gaap	Net Income Loss NetIncomeLoss	335700000	USD
CY2013	us-gaap	Net Income Loss NetIncomeLoss	376200000	USD
CY2014	us-gaap	Net Income Loss NetIncomeLoss	393300000	USD
CY2012	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	319800000	USD
CY2014Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	61800000	USD
CY2014Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	153300000	USD
CY2014Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	60000000	USD
CY2014Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	108000000	USD
CY2013Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	69900000	USD
CY2013Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	65300000	USD
CY2013Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	157600000	USD
CY2013Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	65500000	USD
CY2013	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	358300000	USD
CY2014	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	383100000	USD
CY2012	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-89500000	USD
CY2013	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-97900000	USD
CY2014	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-103600000	USD
CY2012	us-gaap	Operating Income Loss OperatingIncomeLoss	519700000	USD
CY2013Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	120700000	USD
CY2013Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	103200000	USD
CY2013Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	201400000	USD
CY2013Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	108600000	USD
CY2013	us-gaap	Operating Income Loss OperatingIncomeLoss	533900000	USD
CY2014Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	154200000	USD
CY2014Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	103300000	USD
CY2014Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	194800000	USD
CY2014Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	91300000	USD
CY2014	us-gaap	Operating Income Loss OperatingIncomeLoss	543600000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	42000000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	8000000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	1000000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	2000000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	3000000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	7000000	USD
CY2014Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	21000000	USD
CY2012	us-gaap	Operating Leases Rent Expense Contingent Rentals OperatingLeasesRentExpenseContingentRentals	6000000	USD
CY2013	us-gaap	Operating Leases Rent Expense Contingent Rentals OperatingLeasesRentExpenseContingentRentals	0	USD
CY2014	us-gaap	Operating Leases Rent Expense Contingent Rentals OperatingLeasesRentExpenseContingentRentals	0	USD
CY2012	us-gaap	Operating Leases Rent Expense Minimum Rentals OperatingLeasesRentExpenseMinimumRentals	69000000	USD
CY2013	us-gaap	Operating Leases Rent Expense Minimum Rentals OperatingLeasesRentExpenseMinimumRentals	9000000	USD
CY2014	us-gaap	Operating Leases Rent Expense Minimum Rentals OperatingLeasesRentExpenseMinimumRentals	12000000	USD
CY2012	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	75000000	USD
CY2013	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	9000000	USD
CY2014	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	12000000	USD
CY2012	us-gaap	Other Amortization Of Deferred Charges OtherAmortizationOfDeferredCharges	55000000	USD
CY2013	us-gaap	Other Amortization Of Deferred Charges OtherAmortizationOfDeferredCharges	40200000	USD
CY2014	us-gaap	Other Amortization Of Deferred Charges OtherAmortizationOfDeferredCharges	54200000	USD
CY2013Q4	us-gaap	Other Assets Current OtherAssetsCurrent	125700000	USD
CY2014Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	43900000	USD
CY2014Q4	us-gaap	Other Assets Current OtherAssetsCurrent	116900000	USD
CY2013Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	85800000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	0	USD
CY2013	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	600000	USD
CY2014	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-400000	USD
CY2012	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	11900000	USD
CY2013	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	14900000	USD
CY2014	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	6700000	USD
CY2013Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	233800000	USD
CY2014Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	262400000	USD
CY2013Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	273900000	USD
CY2014Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	260100000	USD
CY2013Q4	us-gaap	Other Minority Interests OtherMinorityInterests	1800000	USD
CY2014Q4	us-gaap	Other Minority Interests OtherMinorityInterests	1800000	USD
CY2012	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-700000	USD
CY2013	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	3700000	USD
CY2014	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-2000000	USD
CY2012	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	4000000	USD
CY2013	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	400000	USD
CY2014	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	1800000	USD
CY2013Q4	us-gaap	Other Receivables OtherReceivables	95700000	USD
CY2014Q4	us-gaap	Other Receivables OtherReceivables	80200000	USD
CY2012	us-gaap	Other Sales Revenue Net OtherSalesRevenueNet	56700000	USD
CY2013	us-gaap	Other Sales Revenue Net OtherSalesRevenueNet	71300000	USD
CY2014	us-gaap	Other Sales Revenue Net OtherSalesRevenueNet	66100000	USD
CY2012	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-2600000	USD
CY2013	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	18800000	USD
CY2014	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	14900000	USD
CY2012	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	0	USD
CY2013	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	211000000	USD
CY2014	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	0	USD
CY2012	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	199300000	USD
CY2013	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	208300000	USD
CY2014	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	225800000	USD
CY2012	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	15900000	USD
CY2013	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	11400000	USD
CY2014	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	10200000	USD
CY2012	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1158100000	USD
CY2013	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	798300000	USD
CY2014	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	902800000	USD
CY2013Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	206600000	USD
CY2014Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	421700000	USD
CY2012	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	385000000	USD
CY2013	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	250000000	USD
CY2014	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	812900000	USD
CY2012	us-gaap	Proceeds From Issuance Of Redeemable Preferred Stock ProceedsFromIssuanceOfRedeemablePreferredStock	0	USD
CY2013	us-gaap	Proceeds From Issuance Of Redeemable Preferred Stock ProceedsFromIssuanceOfRedeemablePreferredStock	200000000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	3923100000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	677900000	USD
CY2014	us-gaap	Proceeds From Issuance Of Redeemable Preferred Stock ProceedsFromIssuanceOfRedeemablePreferredStock	0	USD
CY2012	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-8900000	USD
CY2013	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-17400000	USD
CY2014	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-7100000	USD
CY2012	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	164700000	USD
CY2013	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	11900000	USD
CY2013Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	8326500000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	3726200000	USD
CY2014Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	8938400000	USD
CY2013Q4	us-gaap	Property Plant And Equipment Other PropertyPlantAndEquipmentOther	479000000	USD
CY2014Q4	us-gaap	Property Plant And Equipment Other PropertyPlantAndEquipmentOther	509500000	USD
CY2012	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	21900000	USD
CY2013	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	30800000	USD
CY2014	us-gaap	Public Utilities Allowance For Funds Used During Construction Additions PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions	34800000	USD
CY2014	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-138100000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Construction Work In Progress PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress	479100000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	7847500000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	8428900000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	22300000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	22300000	USD
CY2013Q4	us-gaap	Public Utilities Property Plant And Equipment Present Value Of Regulated Asset For Plant Abandonment PublicUtilitiesPropertyPlantAndEquipmentPresentValueOfRegulatedAssetForPlantAbandonment	157800000	USD
CY2014Q4	us-gaap	Public Utilities Property Plant And Equipment Present Value Of Regulated Asset For Plant Abandonment PublicUtilitiesPropertyPlantAndEquipmentPresentValueOfRegulatedAssetForPlantAbandonment	157600000	USD
CY2013Q4	us-gaap	Regulatory Assets RegulatoryAssets	1413200000	USD
CY2014Q4	us-gaap	Regulatory Assets RegulatoryAssets	1783700000	USD
CY2013Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	53900000	USD
CY2014Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	68100000	USD
CY2013Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	1359300000	USD
CY2014Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	1715600000	USD
CY2013Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	821500000	USD
CY2014Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	821200000	USD
CY2013Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	196600000	USD
CY2014Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	200100000	USD
CY2013Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	624900000	USD
CY2014Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	621100000	USD
CY2012	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	1400000	USD
CY2013	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	1500000	USD
CY2014	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	358500000	USD
CY2013Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1780700000	USD
CY2014Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1938000000	USD
CY2012	us-gaap	Revenues Revenues	3094500000	USD
CY2013Q1	us-gaap	Revenues Revenues	859600000	USD
CY2013Q2	us-gaap	Revenues Revenues	718000000	USD
CY2013Q3	us-gaap	Revenues Revenues	866600000	USD
CY2013Q4	us-gaap	Revenues Revenues	832600000	USD
CY2013	us-gaap	Revenues Revenues	3276800000	USD
CY2014Q1	us-gaap	Revenues Revenues	952800000	USD
CY2014Q2	us-gaap	Revenues Revenues	750300000	USD
CY2014Q3	us-gaap	Revenues Revenues	843100000	USD
CY2013Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.002
CY2014Q4	us-gaap	Revenues Revenues	804100000	USD
CY2014	us-gaap	Revenues Revenues	3350300000	USD
CY2014Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.004
CY2013	us-gaap	Shortterm Debt Average Outstanding Amount ShorttermDebtAverageOutstandingAmount	210500000	USD
CY2014	us-gaap	Shortterm Debt Average Outstanding Amount ShorttermDebtAverageOutstandingAmount	255900000	USD
CY2013	us-gaap	Shortterm Debt Maximum Amount Outstanding During Period ShorttermDebtMaximumAmountOutstandingDuringPeriod	293900000	USD
CY2014	us-gaap	Shortterm Debt Maximum Amount Outstanding During Period ShorttermDebtMaximumAmountOutstandingDuringPeriod	353800000	USD
CY2012	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	20195	shares
CY2013	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	-23374	shares
CY2014	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	35547	shares
CY2011Q4	us-gaap	Stockholders Equity StockholdersEquity	3013000000	USD
CY2012Q4	us-gaap	Stockholders Equity StockholdersEquity	3134900000	USD
CY2013Q4	us-gaap	Stockholders Equity StockholdersEquity	3281400000	USD
CY2014Q4	us-gaap	Stockholders Equity StockholdersEquity	3438700000	USD
CY2013Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3483200000	USD
CY2014Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3640500000	USD
CY2012	us-gaap	Stockholders Equity Other StockholdersEquityOther	-1400000	USD
CY2013	us-gaap	Stockholders Equity Other StockholdersEquityOther	-1300000	USD
CY2014	us-gaap	Stockholders Equity Other StockholdersEquityOther	-400000	USD
CY2012	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	98200000	USD
CY2013	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	99600000	USD
CY2014	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	101100000	USD
CY2013Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	19900000	USD
CY2014Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	22400000	USD
CY2011Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	23500000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	700000	USD
CY2013Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2014Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2012	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	23500000	USD
CY2013	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	700000	USD
CY2014	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2012	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	700000	USD
CY2013	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2014	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2012	us-gaap	Unregulated Operating Revenue UnregulatedOperatingRevenue	52200000	USD
CY2013	us-gaap	Unregulated Operating Revenue UnregulatedOperatingRevenue	51700000	USD
CY2014	us-gaap	Unregulated Operating Revenue UnregulatedOperatingRevenue	53100000	USD
CY2012	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	590000000	USD
CY2013	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	620700000	USD
CY2014	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	658300000	USD
CY2012	us-gaap	Weighted Average Number Of Share Outstanding Basic And Diluted WeightedAverageNumberOfShareOutstandingBasicAndDiluted	110800000	shares
CY2013	us-gaap	Weighted Average Number Of Share Outstanding Basic And Diluted WeightedAverageNumberOfShareOutstandingBasicAndDiluted	110800000	shares
CY2014	us-gaap	Weighted Average Number Of Share Outstanding Basic And Diluted WeightedAverageNumberOfShareOutstandingBasicAndDiluted	110800000	shares
CY2014	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes. The balance sheets presentation changed from a utility format to a traditional format. This change revised the order of certain balance sheet line items and did not result in any changes in classification of amounts between line items. Unless otherwise noted, the notes herein exclude discontinued operations for all periods presented, and assets and liabilities held for sale as of December 31, 2014.</font></div></div>
CY2014	us-gaap	Use Of Estimates UseOfEstimates	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The preparation of the financial statements requires management to make estimates and assumptions that affect: (a) the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements; and (b) the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.</font></div></div>

Files In Submission

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$LNT
ALLIANT ENERGY CORP Stock $lnt

2014 Q4 Form 10-K Financial Statement

#000035254115000005 Filed on February 25, 2015

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$LNT ALLIANT ENERGY CORP Stock $lnt

2014 Q4 Form 10-K Financial Statement

#000035254115000005 Filed on February 25, 2015

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$LNT
ALLIANT ENERGY CORP Stock $lnt