Impact to Income Statement from termination of fair value interest rate hedge due to accrued but unpaid interest.

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Cash received from termination of fair value interest rate hedge.

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Fair value of total debt in excess of carrying value.

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Amount of debt securities that contain a provision to retire the debt instrument prior to final maturity, with the payment of fixed call premiums, or in certain cases, at par.

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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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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount as of the balance sheet date of the unamortized adjustment to the carrying value of an interest-bearing hedged item made under an effective interest rate fair value hedge that is amortized upon discontinuation of the interest rate fair value hedge.

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The amount of net gains and losses recognized in income during the period on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges, on derivative instruments designated and qualifying as hedging instruments in cash flow hedges, and on derivative instruments not designated as hedging instruments.

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- Definition

The net gain (loss) included in earnings for the period relating to components of the gain (loss) on interest rate fair value hedging instruments excluded from the assessment of fair value hedge effectiveness.

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Fair value as of the balance sheet date of all interest rate derivatives designated as cash flow hedging instruments.

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Fair value of all derivatives designated as interest rate fair value hedging instruments.

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Aggregate notional amount of all interest rate derivatives designated as hedging instruments in fair value hedges. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

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Amount of unrealized gain (loss) related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

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Financial Instruments (Details) (USD $)	12 Months Ended
Financial Instruments (Details) (USD $)	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Feb. 25, 2010
Earnings Impact [Abstract]
Decrease in interest expense from interest rate hedging	$ 0	$ 2,000,000	$ 8,000,000
Increase in pre-tax income	0	2,000,000	8,000,000
Fair Value of Debt Instruments [Abstract]
Fair value of total debt	10,500,000,000	10,400,000,000
Fair value of total debt in excess of carrying value	1,600,000,000	1,200,000,000
Fixed rate debt securities containing call provisions	303,000,000	303,000,000
Interest Rate Cash Flow Hedges [Abstract]
Change in fair value of cash flow hedges as reported in accumulated other comprehensive loss	2,000,000	3,000,000
Interest rate cash flow hedges outstanding	0	0
Interest Rate Derivatives [Abstract]
Terminated interest rate swap notional amount				250,000,000
Early termination cash received				20,000,000
Cash received fair value of swap				16,000,000
Cash received for accrued but unpaid interest receivable				4,000,000
Interest rate fair value hedges outstanding	0	0
Market and Credit Risk [Abstract]
Collateral for hedging activity	$ 0	$ 0