1.0.0.3 false CONSOLIDATED BALANCE SHEETS (USD $) In Millions 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 5 Current Assets 3 us-gaap_AssetsCurrentAbstract 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 No definition available. false 6 Cash and cash equivalents 4 us-gaap_CashAndCashEquivalentsAtCarryingValue us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 true true 1656000000 1656 false false 2 true true 1807000000 1807 false false No definition available. No authoritative reference available. false 7 Short-term investments 4 us-gaap_HeldToMaturitySecuritiesCurrent us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 2000000 2 false false 2 false true 4000000 4 false false No definition available. No authoritative reference available. false 8 Accounts receivable - trade 4 us-gaap_AccountsReceivableNetCurrent us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 203000000 203 false false 2 false true 241000000 241 false false No definition available. No authoritative reference available. false 9 Receivables from affiliates 4 us-gaap_DueFromAffiliateCurrent us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 184000000 184 false false 2 false true 18000000 18 false false No definition available. No authoritative reference available. false 10 Inventory 4 us-gaap_InventoryNet us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 220000000 220 false false 2 false true 189000000 189 false false No definition available. No authoritative reference available. false 11 Derivative assets 4 us-gaap_DerivativeAssetsCurrent us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 223000000 223 false false 2 false true 170000000 170 false false No definition available. No authoritative reference available. false 12 Restricted cash 4 us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 188000000 188 false false 2 false false 0 0 false false No definition available. No authoritative reference available. false 13 Margin and collateral deposits 4 us-gaap_GoodFaithAndMarginDepositsWithBrokerDealers us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 100000000 100 false false 2 false true 88000000 88 false false No definition available. No authoritative reference available. false 14 Prepaid expenses and other 4 eme_PrepaidExpensesAndOtherCurrentAssets eme false debit instant monetary Sum of the amounts paid in advance for capitalized costs that will be expensed with the passage of time or the occurrence of... false false false false false false false false false 1 false true 106000000 106 false false 2 false true 144000000 144 false false Sum of the amounts paid in advance for capitalized costs that will be expensed with the passage of time or the occurrence of a triggering event, and will be charged against earnings within one year or the normal operating cycle, if longer, combined with the aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet due to materiality considerations. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer). No authoritative reference available. false 15 Total current assets 4 us-gaap_AssetsCurrent us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 2882000000 2882 false false 2 false true 2661000000 2661 false false No definition available. No authoritative reference available. true 16 Investments in Unconsolidated Affiliates 3 us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 353000000 353 false false 2 false true 362000000 362 false false No definition available. No authoritative reference available. false 17 Property, Plant and Equipment 3 us-gaap_PropertyPlantAndEquipmentGross us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 5775000000 5775 false false 2 false true 5643000000 5643 false false No definition available. No authoritative reference available. false 18 Less accumulated depreciation and amortization 4 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 1350000000 1350 false false 2 false true 1241000000 1241 false false No definition available. No authoritative reference available. false 19 Net property, plant and equipment 4 us-gaap_PropertyPlantAndEquipmentNet us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 4425000000 4425 false false 2 false true 4402000000 4402 false false No definition available. No authoritative reference available. true 20 Other Assets 3 us-gaap_OtherAssetsNoncurrentAbstract 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 No definition available. false 21 Deferred financing costs 4 us-gaap_DeferredFinanceCostsNoncurrentNet us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 46000000 46 false false 2 false true 36000000 36 false false No definition available. No authoritative reference available. false 22 Long-term derivative assets 4 us-gaap_DerivativeAssetsNoncurrent us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 165000000 165 false false 2 false true 170000000 170 false false No definition available. No authoritative reference available. false 23 Restricted cash 4 us-gaap_RestrictedCashAndInvestmentsNoncurrent us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 44000000 44 false false 2 false true 43000000 43 false false No definition available. No authoritative reference available. false 24 Rent payments in excess of leverized rent expense under plant operating leases 4 eme_RentPaymentsInExcessOfLevelizedRentExpenseUnderPlantOperatingLeases eme false debit instant monetary Represents prepaid rent, which is the excess of cash rent payments over the amount of rent expense levelized over the term of... false false false false false false false false false 1 false true 991000000 991 false false 2 false true 878000000 878 false false Represents prepaid rent, which is the excess of cash rent payments over the amount of rent expense levelized over the term of each plant operating lease. To the extent that cash rent payments are less than the amount levelized, prepaid rent is reduced. No authoritative reference available. false 25 Other long-term assets 4 us-gaap_OtherAssetsNoncurrent us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 626000000 626 false false 2 false true 528000000 528 false false No definition available. No authoritative reference available. false 26 Total other assets 4 eme_TotalOtherAssetsNoncurrent eme false debit instant monetary Sum of the carrying amounts as of the balance sheet date of all other assets that are expected to be realized in cash, sold... false false false false false false false false false 1 false true 1872000000 1872 false false 2 false true 1655000000 1655 false false Sum of the carrying amounts as of the balance sheet date of all other assets that are expected to be realized in cash, sold or consumed after one year or beyond the normal operating cycle, if longer. No authoritative reference available. true 27 Total Assets 3 us-gaap_Assets us-gaap true debit instant monetary No definition available. false false false false false false false false false 1 false true 9532000000 9532 false false 2 false true 9080000000 9080 false false No definition available. No authoritative reference available. true 29 Current Liabilities 3 us-gaap_LiabilitiesCurrentAbstract 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 No definition available. false 30 Accounts payable 4 us-gaap_AccountsPayableCurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 103000000 103 false false 2 false true 95000000 95 false false No definition available. No authoritative reference available. false 31 Payables to affiliates 4 us-gaap_DueToAffiliateCurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 5000000 5 false false 2 false true 18000000 18 false false No definition available. No authoritative reference available. false 32 Accrued liabilities 4 us-gaap_AccruedLiabilitiesCurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 259000000 259 false false 2 false true 380000000 380 false false No definition available. No authoritative reference available. false 33 Derivative liabilities 4 us-gaap_DerivativeLiabilitiesCurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 7000000 7 false false 2 false true 22000000 22 false false No definition available. No authoritative reference available. false 34 Interest payable 4 us-gaap_InterestPayableCurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 30000000 30 false false 2 false true 30000000 30 false false No definition available. No authoritative reference available. false 35 Deferred taxes 4 us-gaap_DeferredTaxLiabilitiesCurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 95000000 95 false false 2 false true 66000000 66 false false No definition available. No authoritative reference available. false 36 Current maturities of long-term obligations 4 us-gaap_LongTermDebtCurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 39000000 39 false false 2 false true 24000000 24 false false No definition available. No authoritative reference available. false 37 Total current liabilities 4 us-gaap_LiabilitiesCurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 538000000 538 false false 2 false true 635000000 635 false false No definition available. No authoritative reference available. true 38 Long-term obligations net of current maturities 3 us-gaap_LongTermDebtNoncurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 4769000000 4769 false false 2 false true 4638000000 4638 false false No definition available. No authoritative reference available. false 39 Deferred taxes and tax credits 3 us-gaap_DeferredTaxLiabilitiesNoncurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 760000000 760 false false 2 false true 541000000 541 false false No definition available. No authoritative reference available. false 40 Deferred revenues 3 us-gaap_DeferredRevenueAndCreditsNoncurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 65000000 65 false false 2 false true 63000000 63 false false No definition available. No authoritative reference available. false 41 Long-term derivative liabilities 3 us-gaap_DerivativeLiabilitiesNoncurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 13000000 13 false false 2 false true 5000000 5 false false No definition available. No authoritative reference available. false 42 Other long-term liabilities 3 us-gaap_OtherLiabilitiesNoncurrent us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 497000000 497 false false 2 false true 434000000 434 false false No definition available. No authoritative reference available. false 43 Total Liabilities 3 us-gaap_Liabilities us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 6642000000 6642 false false 2 false true 6316000000 6316 false false No definition available. No authoritative reference available. true 45 Equity 3 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract 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 No definition available. false 46 Common stock, par value $0.01 per share; 10,000 shares authorized; 100 shares issued and outstanding as of June 30, 2009 and December 31, 2008 4 us-gaap_CommonStockValue us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 64000000 64 false false 2 false true 64000000 64 false false No definition available. No authoritative reference available. false 47 Additional paid-in capital 4 us-gaap_AdditionalPaidInCapital us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 1337000000 1337 false false 2 false true 1335000000 1335 false false No definition available. No authoritative reference available. false 48 Retained earnings 4 us-gaap_RetainedEarningsAccumulatedDeficit us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 1180000000 1180 false false 2 false true 1085000000 1085 false false No definition available. No authoritative reference available. false 49 Accumulated other comprehensive income 4 us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 230000000 230 false false 2 false true 200000000 200 false false No definition available. No authoritative reference available. false 50 Total EME common shareholder's equity 4 us-gaap_StockholdersEquity us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 2811000000 2811 false false 2 false true 2684000000 2684 false false No definition available. No authoritative reference available. true 51 Noncontrolling Interest 4 us-gaap_MinorityInterest us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 79000000 79 false false 2 false true 80000000 80 false false No definition available. No authoritative reference available. false 52 Total Equity 4 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 false true 2890000000 2890 false false 2 false true 2764000000 2764 false false No definition available. No authoritative reference available. true 53 Total Liabilities and Equity 3 us-gaap_LiabilitiesAndStockholdersEquity us-gaap true credit instant monetary No definition available. false false false false false false false false false 1 true true 9532000000 9532 false false 2 true true 9080000000 9080 false false No definition available. No authoritative reference available. true false 2 47 false Millions UnKnown UnKnown false true