Derivative Financial Instruments (Details 11) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Credit Derivatives [Line Items]
Estimated Fair Value of Derivatives in Net Liability Position	$ 390	$ 1,189
Estimated Fair Value Of Incremental Collateral Provided Upon A One Notch Downgrade In The Company's Credit Rating	54	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	140	231
Derivatives Subject To Credit-Contingent Provisions [Member]
Credit Derivatives [Line Items]
Estimated Fair Value of Derivatives in Net Liability Position	377	1,167
Estimated Fair Value Of Incremental Collateral Provided Upon A One Notch Downgrade In The Company's Credit Rating	54	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	140	231
Derivatives Subject To Credit-Contingent Provisions [Member] \| Fixed Maturities [Member]
Credit Derivatives [Line Items]
Estimated Fair Value of Collateral Provided	288	1,024
Derivatives Subject To Credit-Contingent Provisions [Member] \| Cash [Member]
Credit Derivatives [Line Items]
Estimated Fair Value of Collateral Provided	0	0
Derivatives Not Subject To Credit-Contingent Provisions [Member]
Credit Derivatives [Line Items]
Estimated Fair Value of Derivatives in Net Liability Position	13	22
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
Derivatives Not Subject To Credit-Contingent Provisions [Member] \| Fixed Maturities [Member]
Credit Derivatives [Line Items]
Estimated Fair Value of Collateral Provided	11	0
Derivatives Not Subject To Credit-Contingent Provisions [Member] \| Cash [Member]
Credit Derivatives [Line Items]
Estimated Fair Value of Collateral Provided	0	43
Fixed Maturities [Member]
Credit Derivatives [Line Items]
Estimated Fair Value of Collateral Provided	299	1,024
Cash [Member]
Credit Derivatives [Line Items]
Estimated Fair Value of Collateral Provided	$ 0	$ 43

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The aggregate fair value of assets needed to immediately settle the derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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