1.0.0.3 false CONSOLIDATED STATEMENTS OF INCOME (LOSS) (Constellation Energy Group, Inc. and Subsidiaries) (USD $) In Millions, except Per Share data false 1 $ false false shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 usd Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 usdPerShare Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 false 2 $ false false shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 usd Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 usdPerShare Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 false 3 $ false false shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 usd Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 usdPerShare Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 false 4 $ false false shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 usd Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 usdPerShare Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 4 Revenues 2 us-gaap_RevenuesAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. false 5 Nonregulated revenues 3 us-gaap_SalesRevenueFromEnergyCommoditiesAndServices us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true 3097300000 3097.3 false false 2 true true 4124300000 4124.3 false false 3 true true 6209600000 6209.6 false false 4 true true 7836200000 7836.2 false false No definition available. No authoritative reference available. false 6 Regulated electric revenues 3 us-gaap_ElectricDomesticRegulatedRevenue us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 655700000 655.7 false false 2 false true 448700000 448.7 false false 3 false true 1462500000 1462.5 false false 4 false true 1158000000 1158.0 false false No definition available. No authoritative reference available. false 7 Regulated gas revenues 3 us-gaap_GasDomesticRegulatedRevenue us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 111100000 111.1 false false 2 false true 183100000 183.1 false false 3 false true 495400000 495.4 false false 4 false true 574100000 574.1 false false No definition available. No authoritative reference available. false 8 Total revenues 3 us-gaap_Revenues us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 3864100000 3864.1 false false 2 false true 4756100000 4756.1 false false 3 false true 8167500000 8167.5 false false 4 false true 9568300000 9568.3 false false No definition available. No authoritative reference available. true 9 Expenses 2 us-gaap_CostsAndExpensesAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. false 10 Fuel and purchased energy expenses 3 us-gaap_CostOfGoodsAndServicesEnergyCommoditiesAndServices us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 2631600000 2631.6 false false 2 false true 3559400000 3559.4 false false 3 false true 5904800000 5904.8 false false 4 false true 7302500000 7302.5 false false No definition available. No authoritative reference available. false 11 Operating expenses 3 us-gaap_OperatingExpenses us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 561200000 561.2 false false 2 false true 711500000 711.5 false false 3 false true 1142900000 1142.9 false false 4 false true 1301600000 1301.6 false false No definition available. No authoritative reference available. false 12 Merger termination and strategic alternatives costs 3 ceg_MergerAndStrategicAlternativesCosts ceg false debit duration monetary Amount of costs related to a merger and our pursuit of other strategic alternatives to the merger that were charged to... false false false false false false false false false 1 false true 4000000 4.0 false false 2 false false 0 0 false false 3 false true 46300000 46.3 false false 4 false false 0 0 false false Amount of costs related to a merger and our pursuit of other strategic alternatives to the merger that were charged to expense during the period. No authoritative reference available. false 13 Impairment losses and other costs 3 us-gaap_AssetImpairmentCharges us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 67200000 67.2 false false 2 false false 0 0 false false 3 false true 95800000 95.8 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 14 Workforce reduction costs 3 us-gaap_SeveranceCosts us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 400000 0.4 false false 2 false false 0 0 false false 3 false true 11200000 11.2 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 15 Depreciation, depletion, and amortization 3 us-gaap_DepreciationAndAmortization us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 148900000 148.9 false false 2 false true 141900000 141.9 false false 3 false true 297500000 297.5 false false 4 false true 290200000 290.2 false false No definition available. No authoritative reference available. false 16 Accretion of asset retirement obligations 3 us-gaap_AssetRetirementObligationAccretionExpense us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 18200000 18.2 false false 2 false true 17000000 17.0 false false 3 false true 36100000 36.1 false false 4 false true 33600000 33.6 false false No definition available. No authoritative reference available. false 17 Taxes other than income taxes 3 us-gaap_TaxesExcludingIncomeAndExciseTaxes us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 72400000 72.4 false false 2 false true 71100000 71.1 false false 3 false true 150300000 150.3 false false 4 false true 145900000 145.9 false false No definition available. No authoritative reference available. false 18 Total expenses 3 us-gaap_CostsAndExpenses us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 3503900000 3503.9 false false 2 false true 4500900000 4500.9 false false 3 false true 7684900000 7684.9 false false 4 false true 9073800000 9073.8 false false No definition available. No authoritative reference available. true 19 Net (loss) gain on divestitures 2 us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -129600000 -129.6 false false 2 false true 76500000 76.5 false false 3 false true -464100000 -464.1 false false 4 false true 91500000 91.5 false false No definition available. No authoritative reference available. false 20 Income from Operations 2 us-gaap_OperatingIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 230600000 230.6 false false 2 false true 331700000 331.7 false false 3 false true 18500000 18.5 false false 4 false true 586000000 586.0 false false No definition available. No authoritative reference available. true 21 Other Income (Expense) 2 us-gaap_NonoperatingIncomeExpense us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 12100000 12.1 false false 2 false true 15300000 15.3 false false 3 false true -15400000 -15.4 false false 4 false true 58000000 58.0 false false No definition available. No authoritative reference available. false 22 Fixed Charges: 2 ceg_FixedChargesAbstract ceg false na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. false 23 Interest expense 3 us-gaap_InterestCostsIncurred us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 133200000 133.2 false false 2 false true 73500000 73.5 false false 3 false true 277100000 277.1 false false 4 false true 152300000 152.3 false false No definition available. No authoritative reference available. false 24 Interest capitalized and allowance for borrowed funds used during construction 3 ceg_InterestCapitalizedAndAllowanceForBorrowedFundsUsedDuringConstruction ceg false credit duration monetary The balance consists of interest capitalized during the period for the nonregulated business and the allowance for borrowed... false false false false false false false false false 1 false true -21600000 -21.6 false false 2 false true -8600000 -8.6 false false 3 false true -43200000 -43.2 false false 4 false true -15700000 -15.7 false false The balance consists of interest capitalized during the period for the nonregulated business and the allowance for borrowed funds used during construction in the regulated business during the period, which may be reflected as a reduction of interest expense. No authoritative reference available. false 25 Total fixed charges 3 ceg_FixedCharges ceg false debit duration monetary The aggregate interest expense incurred on all borrowings, net of capitalized interest and allowance for borrowed funds used... false false false false false false false false false 1 false true 111600000 111.6 false false 2 false true 64900000 64.9 false false 3 false true 233900000 233.9 false false 4 false true 136600000 136.6 false false The aggregate interest expense incurred on all borrowings, net of capitalized interest and allowance for borrowed funds used during construction. No authoritative reference available. true 26 Income (Loss) from Continuing Operations Before Income Taxes 2 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 131100000 131.1 false false 2 false true 282100000 282.1 false false 3 false true -230800000 -230.8 false false 4 false true 507400000 507.4 false false No definition available. No authoritative reference available. true 27 Income Tax Expense (Benefit) 2 us-gaap_IncomeTaxExpenseBenefit us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 102800000 102.8 false false 2 false true 107100000 107.1 false false 3 false true -139400000 -139.4 false false 4 false true 183000000 183.0 false false No definition available. No authoritative reference available. false 28 Net Income (Loss) 2 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 28300000 28.3 false false 2 false true 175000000 175.0 false false 3 false true -91400000 -91.4 false false 4 false true 324400000 324.4 false false No definition available. No authoritative reference available. true 29 Less: Net Income Attributable to Noncontrolling Interests and BGE Preference Stock Dividends 2 ceg_NetIncomeLossAttributableToNoncontrollingInterestAndPreferredStockDividendsAndOtherAdjustments ceg false debit duration monetary The portion of net income (loss) attributable to the noncontrolling interest (if any) deducted in order to derive the portion... false false false false false false false false false 1 false true 20200000 20.2 false false 2 false true 3500000 3.5 false false 3 false true 24000000 24.0 false false 4 false true 7200000 7.2 false false The portion of net income (loss) attributable to the noncontrolling interest (if any) deducted in order to derive the portion attributable to the parent combined with the aggregate value of preferred stock dividends and other adjustments necessary to derive net income apportioned to common stockholders. No authoritative reference available. false 30 Net Income (Loss) Attributable to Common Stock 2 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true 8100000 8.1 false false 2 true true 171500000 171.5 false false 3 true true -115400000 -115.4 false false 4 true true 317200000 317.2 false false No definition available. No authoritative reference available. true 31 Average Shares of Common Stock Outstanding - Basic (in shares) 2 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic us-gaap true na duration shares No definition available. false false false false false false false false false 1 false true 199200000 199.2 false false 2 false true 178400000 178.4 false false 3 false true 198900000 198.9 false false 4 false true 178300000 178.3 false false No definition available. No authoritative reference available. false 32 Average Shares of Common Stock Outstanding - Diluted (in shares) 2 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding us-gaap true na duration shares No definition available. false false false false false false false false false 1 false true 200000000 200.0 false false 2 false true 180200000 180.2 false false 3 false true 198900000 198.9 false false 4 false true 180200000 180.2 false false No definition available. No authoritative reference available. false 33 Earnings (Loss) Per Common Share - Basic (in dollars per share) 2 us-gaap_EarningsPerShareBasic us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 0.04 0.04 false false 2 true true 0.96 0.96 false false 3 true true -0.58 -0.58 false false 4 true true 1.78 1.78 false false No definition available. No authoritative reference available. false 34 Earnings (Loss) Per Common Share - Diluted (in dollars per share) 2 us-gaap_EarningsPerShareDiluted us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 0.04 0.04 false false 2 true true 0.95 0.95 false false 3 true true -0.58 -0.58 false false 4 true true 1.76 1.76 false false No definition available. No authoritative reference available. false 35 Dividends Declared Per Common Share (in dollars per share) 2 us-gaap_CommonStockDividendsPerShareDeclared us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 0.24 0.24 false false 2 true true 0.4775 0.4775 false false 3 true true 0.48 0.48 false false 4 true true 0.955 0.955 false false No definition available. No authoritative reference available. false false 4 32 false HundredThousands HundredThousands NoRounding false true