1.0.0.3 false CONSOLIDATED STATEMENTS OF COMPREHENSIVE 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 COMPREHENSIVE INCOME 0 us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract 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 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 true true 194000000 194 false false 2 true true 501000000 501 false false 3 true true 413000000 413 false false No definition available. No authoritative reference available. false 5 Pension and postretirement benefits other than pensions: 2 us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract 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 6 Prior service adjustment, net of tax 3 us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostsCreditArisingDuringPeriodNetOfTax us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 1000000 1 false false 2 false true 3000000 3 false false 3 false true -1000000 -1 false false No definition available. No authoritative reference available. false 7 Net gain (loss) adjustment, net of tax expense (benefit) of $6, $(26) and $4 for 2009, 2008 and 2007, respectively 3 us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 10000000 10 false false 2 false true -41000000 -41 false false 3 false true 7000000 7 false false No definition available. No authoritative reference available. false 8 Amortization of net loss and prior service adjustment included in expense, net of tax 3 us-gaap_OtherComprehensiveIncomeReclassificationOfDefinedBenefitPlansNetGainLossRecognizedInNetPeriodicBenefitCostNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 2000000 2 false false 2 false true 1000000 1 false false 3 false true 1000000 1 false false No definition available. No authoritative reference available. false 9 Unrealized gains (losses) on derivatives qualified as cash flow hedges: 2 us-gaap_OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPeriodIncreaseDecreaseAbstract 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 10 Unrealized holding gains (losses) arising during period, net of income tax expense (benefit) of $36, $138 and $(160) for 2009, 2008 and 2007, respectively 3 us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 43000000 43 false false 2 false true 211000000 211 false false 3 false true -235000000 -235 false false No definition available. No authoritative reference available. false 11 Reclassification adjustments included in net income, net of income tax expense (benefit) of $124, $(58) and $(45) for 2009, 2008 and 2007, respectively 3 us-gaap_OtherComprehensiveIncomeReclassificationAdjustmentOnDerivativesIncludedInNetIncomeNetOfTax us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -178000000 -178 false false 2 false true 89000000 89 false false 3 false true 64000000 64 false false No definition available. No authoritative reference available. false 12 Other comprehensive income (loss) 2 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true -122000000 -122 false false 2 false true 263000000 263 false false 3 false true -164000000 -164 false false No definition available. No authoritative reference available. true 13 Comprehensive Income 1 us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 72000000 72 false false 2 false true 764000000 764 false false 3 false true 249000000 249 false false No definition available. No authoritative reference available. true 14 Comprehensive Loss Attributable to Noncontrolling Interests 1 us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest 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 15 Comprehensive Income Attributable to EME Common Shareholders 1 us-gaap_ComprehensiveIncomeNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true 75000000 75 false false 2 true true 764000000 764 false false 3 true true 250000000 250 false false No definition available. No authoritative reference available. true false 3 13 false Millions UnKnown UnKnown false true