Investments (Net Realized Gains (Losses) And The Losses Included In Net Realized Gains (Losses) And OCI) (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Investments [Abstract]
OTTI on fixed maturities, gross	$ (30)	$ (39)	$ (41)	$ (107)
OTTI on fixed maturities recognized in OCI (pre-tax)	11	20	13	65
OTTI on fixed maturities, net	(19)	(19)	(28)	(42)
Fixed maturities, Gross realized gains excluding OTTI	92	138	309	434
Fixed maturities, Gross realized losses excluding OTTI	(53)	(6)	(138)	(121)
Total fixed maturities	20	113	143	271
OTTI on equity securities	(1)		(1)
Equity securities, Gross realized gains excluding OTTI		8	12	85
Equity securities, Gross realized losses excluding OTTI	(1)	(1)	(2)	(1)
Total equity securities	(2)	7	9	84
OTTI on other investments			(3)	(13)
Foreign exchange gains (losses)	20	(62)	(89)	(10)
Investment and embedded derivative instruments	(89)	(1)	(157)	23
Fair value adjustments on insurance derivative	(926)	25	(925)	(180)
S&P put options and futures	220	(110)	152	(26)
Other derivative instruments	2	(14)	(1)	(19)
Other	(5)	(8)	(7)	(3)
Net realized gains (losses)	$ (760)	$ (50)	$ (878)	$ 127

Aggregate gains on all equity securities recognized in earnings during the period, before tax effects excluding other than temporary impairments.

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Aggregate loss on all equity securities recognized in earnings during the period, before tax effects excluding other than temporary impairments.

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Net realized gains/losses and OCI relating to equity securities as a result of conditions which caused the company to conclude the decline in the fair value of certain investments was other than temporary.

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Aggregate gain/loss relating to fair value adjustments on insurance derivative instruments recognized in earnings during the period, before tax effects.

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Aggregate gain on all equity securities recognized in earnings during the period, before tax effects excluding other than temporary impairments.

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Aggregate loss on all fixed maturities securities recognized in earnings during the period, before tax effects excluding other than temporary impairments.

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Net realized gains/losses and OCI relating to fixed maturities as a result of conditions which caused the company to conclude the decline in the fair value of certain investments was other than temporary.

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The gross decline in fair value that is deemed to be "other than temporary" as it relates to fixed maturities.

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The decline in fair value that is deemed to be "other than temporary" reflected in other comprehensive income (pre-tax) as it relates to fixed maturities.

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The net decline in fair value that is deemed to be "other than temporary" as it relates to fixed maturities (net of other than temporary impairments in other comprehensive income).

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Aggregate gain/loss on all investment and embedded derivative instruments recognized in earnings during the period, before tax effects.

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The net realized gains or losses on investments, derivative instruments, and foreign exchange recognized during the period.

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Aggregate gain/loss on all other derivative instruments recognized in earnings during the period, before tax effects

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The decline in fair value that is deemed to be "other than temporary" as it relates to other investments.

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Aggregate gain/loss on all other investments recognized in earnings during the period, before tax effects.

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Aggregate gain/loss on all Standard and Poors put options and futures recognized in earnings during the period, before tax effects.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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

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The aggregate foreign currency transaction gain (loss) (both realized and unrealized) included in determining net income for the reporting period. Excludes foreign currency transactions designated as hedges of net investment in a foreign entity and intercompany foreign currency transactions that are of a long-term nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements. For certain enterprises, primarily banks, that are dealers in foreign exchange, foreign currency transaction gains (losses) may be disclosed as dealer gains (losses).

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