1.0.0.3 false CONSOLIDATED STATEMENTS OF INCOME (USD $) In Millions false 1 $ false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 false 2 $ false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 false 3 $ false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 2 CONSOLIDATED STATEMENTS OF INCOME 0 us-gaap_IncomeStatementAbstract 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 No definition available. false 3 Operating Revenues 1 us-gaap_ElectricalGenerationRevenue us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true 2377000000 2377 false false 2 true true 2811000000 2811 false false 3 true true 2580000000 2580 false false No definition available. No authoritative reference available. false 4 Operating Expenses 1 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 No definition available. false 5 Fuel 2 us-gaap_FuelCosts us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 796000000 796 false false 2 false true 747000000 747 false false 3 false true 684000000 684 false false No definition available. No authoritative reference available. false 6 Plant operations 2 us-gaap_OtherCostAndExpenseOperating us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 579000000 579 false false 2 false true 621000000 621 false false 3 false true 584000000 584 false false No definition available. No authoritative reference available. false 7 Plant operating leases 2 us-gaap_SaleLeasebackTransactionRentExpense us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 177000000 177 false false 2 false true 176000000 176 false false 3 false true 176000000 176 false false No definition available. No authoritative reference available. false 8 Depreciation and amortization 2 us-gaap_DepreciationDepletionAndAmortization us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 236000000 236 false false 2 false true 194000000 194 false false 3 false true 162000000 162 false false No definition available. No authoritative reference available. false 9 Gain on buyout of contract, loss on termination of contract, asset write-down and other charges and credits, net (Notes 1, 5 and 13) 2 us-gaap_GainLossOnContractTermination us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 4000000 4 false false 2 false true 14000000 14 false false 3 false true 6000000 6 false false No definition available. No authoritative reference available. false 10 Administrative and general 2 us-gaap_GeneralAndAdministrativeExpense us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 196000000 196 false false 2 false true 207000000 207 false false 3 false true 204000000 204 false false No definition available. No authoritative reference available. false 11 Total operating expenses 2 us-gaap_CostsAndExpenses us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 1988000000 1988 false false 2 false true 1959000000 1959 false false 3 false true 1816000000 1816 false false No definition available. No authoritative reference available. true 12 Operating income 1 us-gaap_OperatingIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 389000000 389 false false 2 false true 852000000 852 false false 3 false true 764000000 764 false false No definition available. No authoritative reference available. true 13 Other Income (Expense) 1 us-gaap_NonoperatingIncomeExpenseAbstract 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 No definition available. false 14 Equity in income from unconsolidated affiliates 2 us-gaap_IncomeLossFromEquityMethodInvestments us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 100000000 100 false false 2 false true 122000000 122 false false 3 false true 200000000 200 false false No definition available. No authoritative reference available. false 15 Dividend income 2 us-gaap_OtherInterestAndDividendIncome us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 12000000 12 false false 2 false true 10000000 10 false false 3 false true 12000000 12 false false No definition available. No authoritative reference available. false 16 Interest income 2 us-gaap_InvestmentIncomeInterest us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 7000000 7 false false 2 false true 26000000 26 false false 3 false true 85000000 85 false false No definition available. No authoritative reference available. false 17 Interest expense 2 us-gaap_InterestExpense us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -296000000 -296 false false 2 false true -279000000 -279 false false 3 false true -273000000 -273 false false No definition available. No authoritative reference available. false 18 Loss on early extinguishment of debt 2 us-gaap_GainsLossesOnExtinguishmentOfDebt us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true -160000000 -160 false false No definition available. No authoritative reference available. false 19 Other income (expense), net 2 us-gaap_OtherNonoperatingIncomeExpense us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 5000000 5 false false 2 false true 12000000 12 false false 3 false true 6000000 6 false false No definition available. No authoritative reference available. false 20 Total 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 -172000000 -172 false false 2 false true -109000000 -109 false false 3 false true -130000000 -130 false false No definition available. No authoritative reference available. true 21 Income from continuing operations before income taxes 1 eme_IncomeFromContinuingOperationsBeforeIncomeTaxes eme false credit duration monetary Sum of operating profit and non operating income (expense) before income taxes and noncontrolling interest. false false false false false false false false false 1 false true 217000000 217 false false 2 false true 743000000 743 false false 3 false true 634000000 634 false false Sum of operating profit and non operating income (expense) before income taxes and noncontrolling interest. No authoritative reference available. true 22 Provision for income taxes 1 us-gaap_IncomeTaxExpenseBenefit us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 16000000 16 false false 2 false true 243000000 243 false false 3 false true 219000000 219 false false No definition available. No authoritative reference available. false 23 Income From Continuing Operations 1 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 201000000 201 false false 2 false true 500000000 500 false false 3 false true 415000000 415 false false No definition available. No authoritative reference available. true 24 Income (loss) from operations of discontinued subsidiaries, net of tax (Note 7) 1 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -7000000 -7 false false 2 false true 1000000 1 false false 3 false true -2000000 -2 false false No definition available. No authoritative reference available. false 25 Net Income 1 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 194000000 194 false false 2 false true 501000000 501 false false 3 false true 413000000 413 false false No definition available. No authoritative reference available. true 26 Net Loss Attributable to Noncontrolling Interests 1 us-gaap_NetIncomeLossAttributableToNoncontrollingInterest us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 3000000 3 false false 2 false false 0 0 false false 3 false true 1000000 1 false false No definition available. No authoritative reference available. false 27 Net Income Attributable to EME Common Shareholders 1 us-gaap_NetIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 197000000 197 false false 2 false true 501000000 501 false false 3 false true 414000000 414 false false No definition available. No authoritative reference available. true 28 Amounts Attributable to EME Common Shareholders 1 us-gaap_IncomeAmountsAttributableToReportingEntityDisclosuresAbstract 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 No definition available. false 29 Income from continuing operations, net of tax 2 us-gaap_IncomeLossFromContinuingOperations us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 204000000 204 false false 2 false true 500000000 500 false false 3 false true 416000000 416 false false No definition available. No authoritative reference available. false 30 Income (loss) from discontinued operations, net of tax 2 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -7000000 -7 false false 2 false true 1000000 1 false false 3 false true -2000000 -2 false false No definition available. No authoritative reference available. false 31 Net Income Attributable to EME Common Shareholders 2 us-gaap_NetIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true 197000000 197 false false 2 true true 501000000 501 false false 3 true true 414000000 414 false false No definition available. No authoritative reference available. true false 3 30 false Millions UnKnown UnKnown false true