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12/31/2009
USD ($)
$As_Of_12_31_200963http://www.sec.gov/CIK0000093751instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseDerivatives Designated as Hedges [Member]us-gaap_TradingActivityGainsAndLossesByIncomeStatementLocationAxisxbrldihttp://xbrl.org/2006/xbrldistt_DerivativesDesignedAsHedgesMemberus-gaap_TradingActivityGainsAndLossesByIncomeStatementLocationAxisexplicitMemberfalsefalseInterest Rate Contracts [Member]us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_InterestRateContractMemberus-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalse19false0us-gaap_DerivativeAssetDesignatedAsHedgingInstrumentFairValueus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse3200000032falsefalsefalsefalsefalse2truefalsefalse2000000020falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFair value of a derivative asset (or nonderivative instrument) that is designated and qualifies as a hedging instrument, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 205G
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44C
-Subparagraph a
-Clause 1
falsefalse20false0us-gaap_DerivativeLiabilityDesignatedAsHedgingInstrumentFairValueus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1t
ruefalsefalse228000000228falsetruefalsefalsefalse2truefalsefalse206000000206falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFair value of a derivative liability (or nonderivative instrument) that is designated and qualifies as a hedging instrument, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 205G
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44C
-Subparagraph a
-Clause 1
falsefalse220Derivative Financial Instruments (Schedule of the Fair Values of Derivative Financial Instruments) (Details) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue
