v2.4.0.6

Derivative Instruments (Textuals) (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended	3 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Mar. 31, 2012 Interest Rate Swap [Member]
Derivative Instruments (Textuals) [Abstract]
Maximum length of time hedging using interest rate derivative instruments			11 years
Derivative, Net Liability Position, Aggregate Fair Value	$ 4,000,000		$ 4,000,000
Collateral Already Posted, Aggregate Fair Value	2,000,000		2,000,000
Additional Collateral, Aggregate Fair Value	0		0
Early Repayment of Senior Debt					1,200,000,000
Notional Amount Interest Rate Derivative Underlying Debt Repaid During Period					1,000,000,000
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net				91,000,000	91,000,000
Cumulative cash flow hedge losses remaining in AOCI			236,000,000		172,000,000
Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	8,000,000	7,000,000	23,000,000	24,000,000
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months			21,000,000
Losses from interest rate contracts reclassified from OCI into earnings				15,000,000
Notional Amount Interest Rate Derivative Underlying Debt Repaid					4,100,000,000
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	0	(3,000,000)	(14,000,000)	(149,000,000)		156,000,000
Interest Rate Derivative Liabilities, Fair Value on Settlement Date [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments, realized				142,000,000
Gain Loss On Interest Rate Derivative Instruments Not Designated As Hedging Instruments, Unrealized				$ 14,000,000

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Gain Loss On Interest Rate Derivative Instruments Not Designated As Hedging Instruments, Unrealized

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Losses from interest rate contracts reclassified from OCI into earnings

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Notional Amount Interest Rate Derivative Underlying Debt Repaid

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The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

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The amount of net gains or losses on a cash flow hedge reclassified in the period to earnings from accumulated other comprehensive income.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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Amount of gain (loss) included in earnings for the period from the increase (decrease) in fair value of interest rate derivatives not designated as hedging instruments.

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Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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