Fair Value (Details Textuals) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Fair Value (Textuals) [Abstract]
Additions to MSRs	$ 46	$ 169	$ 138	$ 275
Reduction due to loan payments or sales	(32)	(31)	(92)	(117)
Changes in valuation model inputs or assumptions affecting MSRs	(292)	(91)	(310)	(329)
Call options in equity securities	(65)		(65)		(62)
Call options in fixed maturity securities	3		3		5
Transfers between Levels 1 and 2	not significant	not significant	not significant	not significant
Fixed maturity securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers Into Level 3	862	367	604	1,475
Transfers Out of Level 3	(1,432)	(1,240)	(4,718)	(1,413)
Separate account assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers Into Level 3	11	9	18	31
Transfers Out of Level 3	(176)	(75)	(258)	(224)
Derivatives [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers Out of Level 3	0		(101)
Non Recurring [Member] \| Other limited partnership interests [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unfunded commitment for investments	1	25	1	25
Non Recurring [Member] \| Real estate joint ventures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unfunded commitment for investments	$ 0	$ 7	$ 0	$ 7

The increase during the reporting period in the cumulative value of servicing rights. This increase is the result of the origination or acquisition of mortgage servicing rights.

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- Definition

Call options embedded in equity host contracts that are classified as equity securities. The call options give the issuer the right to reacquire the equity instrument for cash or other assets.

+ Details

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- Definition

Call options embedded in fixed maturity host contracts that are classified as fixed maturity securities. The call options give the issuer the right to reacquire the fixed maturity instrument for cash or other assets.

+ Details

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- Definition

This element represents the change in MSRs measured at fair value on a recurring basis using unobservable inputs (Level 3), due to changes in valuation model inputs or assumptions.

+ Details

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- Definition

Fair Value Textuals Abstract.

+ Details

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- Definition

This caption represents the reduction to capitalized mortgage servicing rights from loan repayments or sales during the period.

+ Details

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- Definition

Represents transfers between Levels 1 and 2 during the reporting period.

+ Details

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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.

+ Details

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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.

+ Details

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- Definition

The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 6A

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=SL6742756-110258

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- Definition

Transfers into assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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- Definition

Transfers out of assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

+ References

+ Details

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