Derivative Financial Instruments (Details 11) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Credit Risk
Estimated Fair Value of Derivatives in Net Liability Position	$ 697	$ 1,189
Estimated Fair Value of Collateral Provided Included In Fixed Maturity Securities	412	1,024
Estimated Fair Value Of Collateral Provided Included In Cash	1	43
Estimated Fair Value Of Incremental Collateral Provided Upon A One Notch Downgrade In The Company's Credit Rating	93	99
Estimated Fair Value Of Incremental Collateral Provided Upon A Downgrade In The Company's Credit Rating to a Level that Triggers Full Overnight Collateralization or Termination of the Derivative Position	223	231
Derivatives Subject To Credit-Contingent Provisions [Member]
Credit Risk
Estimated Fair Value of Derivatives in Net Liability Position	693	1,167
Estimated Fair Value of Collateral Provided Included In Fixed Maturity Securities	404	1,024
Estimated Fair Value Of Collateral Provided Included In Cash	0	0
Estimated Fair Value Of Incremental Collateral Provided Upon A One Notch Downgrade In The Company's Credit Rating	93	99
Estimated Fair Value Of Incremental Collateral Provided Upon A Downgrade In The Company's Credit Rating to a Level that Triggers Full Overnight Collateralization or Termination of the Derivative Position	223	231
Derivatives Not Subject To Credit-Contingent Provisions [Member]
Credit Risk
Estimated Fair Value of Derivatives in Net Liability Position	4	22
Estimated Fair Value of Collateral Provided Included In Fixed Maturity Securities	8	0
Estimated Fair Value Of Collateral Provided Included In Cash	1	43
Estimated Fair Value Of Incremental Collateral Provided Upon A One Notch Downgrade In The Company's Credit Rating	0	0
Estimated Fair Value Of Incremental Collateral Provided Upon A Downgrade In The Company's Credit Rating to a Level that Triggers Full Overnight Collateralization or Termination of the Derivative Position	$ 0	$ 0

Credit Risk Abstract.

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- Definition

The aggregate estimated fair value amounts of derivative instruments that are subject to or not subject to credit-contingent provisions 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 estimated fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain or loss on that instrument.

+ Details

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- Definition

The aggregate cash amounts of collateral provided for derivative instruments that are subject to or not subject to credit-contingent provisions that are in a net liability position at the end of the reporting period. The estimated fair value amounts are included in cash.

+ Details

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- Definition

The aggregate estimated fair value amounts of collateral provided for derivative instruments that are subject to or not subject to credit-contingent provisions that are in a net liability position at the end of the reporting period. The estimated fair value amounts are included in fixed maturity securities.

+ Details

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- Definition

The aggregate estimated fair value amounts of incremental collateral to be provided for derivative instruments that are subject to or not subject to credit-contingent provisions that are in a net liability position at the end of the reporting period if a downgrade in the Company's credit rating goes to a level that triggers full overnight collateralization or termination of the derivative position.

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- Definition

The aggregate estimated fair value amounts of incremental collateral to be provided for derivative instruments that are subject to or not subject to credit-contingent provisions that are in a net liability position at the end of the reporting period if the Company's credit rating has a one notch downgrade.

+ Details

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