1.0.0.3 false CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (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 false 4 $ false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 5 Net Income 3 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true 52000000 52 false false 2 true true 208000000 208 false false 3 true true 147000000 147 false false 4 true true 425000000 425 false false No definition available. No authoritative reference available. false 7 Pension and postretirement benefits other than pensions: 4 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 4 false false 0 0 false false No definition available. false 8 Amortization of net loss and prior service adjustment included in expense, net of tax 5 us-gaap_OtherComprehensiveIncomeReclassificationOfDefinedBenefitPlansNetGainLossRecognizedInNetPeriodicBenefitCostNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 1000000 1 false false 2 false false 0 0 false false 3 false true 2000000 2 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 9 Unrealized gains (losses) on derivatives qualified as cash flow hedges: 4 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 4 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 $(4) and $357 for the three months and $44 and $53 for the nine months ended September 30, 2009 and 2008, respectively 5 us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax 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 535000000 535 false false 3 false true 56000000 56 false false 4 false true 81000000 81 false false No definition available. No authoritative reference available. false 11 Reclassification adjustments included in net income, net of income tax expense (benefit) of $52 and $44 for the three months and $75 and $(45) for the nine months ended September 30, 2009 and 2008, respectively 5 us-gaap_OtherComprehensiveIncomeReclassificationAdjustmentOnDerivativesIncludedInNetIncomeNetOfTax us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -72000000 -72 false false 2 false true -66000000 -66 false false 3 false true -104000000 -104 false false 4 false true 69000000 69 false false No definition available. No authoritative reference available. false 12 Other comprehensive income (loss) 4 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true -76000000 -76 false false 2 false true 469000000 469 false false 3 false true -46000000 -46 false false 4 false true 150000000 150 false false No definition available. No authoritative reference available. true 13 Comprehensive Income (Loss) 3 us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -24000000 -24 false false 2 false true 677000000 677 false false 3 false true 101000000 101 false false 4 false true 575000000 575 false false No definition available. No authoritative reference available. true 14 Comprehensive Loss Attributable to Noncontrolling Interest 3 us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest 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 1000000 1 false false 3 false true 2000000 2 false false 4 false true 1000000 1 false false No definition available. No authoritative reference available. false 15 Comprehensive Income (Loss) Attributable to Common Shareholders of EME 3 us-gaap_ComprehensiveIncomeNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true -23000000 -23 false false 2 true true 678000000 678 false false 3 true true 103000000 103 false false 4 true true 576000000 576 false false No definition available. No authoritative reference available. true false 4 10 false Millions UnKnown UnKnown false true