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 3161700000 3161.7 false false 2 true true 4351000000 4351.0 false false 3 true true 9371300000 9371.3 false false 4 true true 12187200000 12187.2 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 788300000 788.3 false false 2 false true 822300000 822.3 false false 3 false true 2250800000 2250.8 false false 4 false true 1980300000 1980.3 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 77700000 77.7 false false 2 false true 150300000 150.3 false false 3 false true 573100000 573.1 false false 4 false true 724400000 724.4 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 4027700000 4027.7 false false 2 false true 5323600000 5323.6 false false 3 false true 12195200000 12195.2 false false 4 false true 14891900000 14891.9 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 2650400000 2650.4 false false 2 false true 4318000000 4318.0 false false 3 false true 8555200000 8555.2 false false 4 false true 11620500000 11620.5 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 587700000 587.7 false false 2 false true 482900000 482.9 false false 3 false true 1730600000 1730.6 false false 4 false true 1784500000 1784.5 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 4900000 4.9 false false 2 false true 39200000 39.2 false false 3 false true 51200000 51.2 false false 4 false true 39200000 39.2 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 7500000 7.5 false false 2 false true 477100000 477.1 false false 3 false true 103300000 103.3 false false 4 false true 477100000 477.1 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 true 2200000 2.2 false false 3 false true 11600000 11.6 false false 4 false true 2200000 2.2 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 149300000 149.3 false false 2 false true 134300000 134.3 false false 3 false true 446800000 446.8 false false 4 false true 424500000 424.5 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 18500000 18.5 false false 2 false true 17200000 17.2 false false 3 false true 54600000 54.6 false false 4 false true 50800000 50.8 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 74400000 74.4 false false 2 false true 81100000 81.1 false false 3 false true 224700000 224.7 false false 4 false true 227000000 227.0 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 3493100000 3493.1 false false 2 false true 5552000000 5552.0 false false 3 false true 11178000000 11178.0 false false 4 false true 14625800000 14625.8 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 -300000 -0.3 false false 2 false false 0 0 false false 3 false true -464400000 -464.4 false false 4 false true 91500000 91.5 false false No definition available. No authoritative reference available. false 20 Income (Loss) 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 534300000 534.3 false false 2 false true -228400000 -228.4 false false 3 false true 552800000 552.8 false false 4 false true 357600000 357.6 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 38700000 38.7 false false 2 false true -15800000 -15.8 false false 3 false true 23300000 23.3 false false 4 false true 42200000 42.2 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 129700000 129.7 false false 2 false true 100000000 100.0 false false 3 false true 406800000 406.8 false false 4 false true 252300000 252.3 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 -22500000 -22.5 false false 2 false true -10500000 -10.5 false false 3 false true -65700000 -65.7 false false 4 false true -26200000 -26.2 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 107200000 107.2 false false 2 false true 89500000 89.5 false false 3 false true 341100000 341.1 false false 4 false true 226100000 226.1 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 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 465800000 465.8 false false 2 false true -333700000 -333.7 false false 3 false true 235000000 235.0 false false 4 false true 173700000 173.7 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 298400000 298.4 false false 2 false true -111600000 -111.6 false false 3 false true 159000000 159.0 false false 4 false true 71400000 71.4 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 167400000 167.4 false false 2 false true -222100000 -222.1 false false 3 false true 76000000 76.0 false false 4 false true 102300000 102.3 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 29800000 29.8 false false 2 false true 3600000 3.6 false false 3 false true 53800000 53.8 false false 4 false true 10800000 10.8 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 137600000 137.6 false false 2 true true -225700000 -225.7 false false 3 true true 22200000 22.2 false false 4 true true 91500000 91.5 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 199600000 199.6 false false 2 false true 178400000 178.4 false false 3 false true 199100000 199.1 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 200800000 200.8 false false 2 false true 179500000 179.5 false false 3 false true 199900000 199.9 false false 4 false true 180000000 180.0 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 0.69 0.69 false false 2 true true -1.27 -1.27 false false 3 true true 0.11 0.11 false false 4 true true 0.51 0.51 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 0.69 0.69 false false 2 true true -1.27 -1.27 false false 3 true true 0.11 0.11 false false 4 true true 0.51 0.51 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 0.72 0.72 false false 4 true true 1.4325 1.4325 false false No definition available. No authoritative reference available. false false 4 32 false HundredThousands HundredThousands NoRounding false true