Invested Assets (Details 5) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Realized investment gains and losses [Abstract]
Fixed maturities, Gross realized gains	$ 25	$ 14	$ 48	$ 71
Fixed maturities, Gross realized losses	(10)	(6)	(25)	(17)
Fixed maturities, Other-than-temporary impairment losses	(1)	0	(1)	(3)
Total fixed maturities	14	8	22	51
Equity securities, Gross realized gains	16	18	45	30
Equity securities, Gross realized losses	0	0	(1)	(1)
Equity securities, Other-than-temporary impairment losses	(6)	0	(22)	(6)
Total equity securities	10	18	22	23
Other invested assets	47	28	256	197
Total Realized Investment Gains, Net	$ 71	$ 54	$ 300	$ 271

The gross realized gain or loss, net, for equity securities included in earnings for the period.

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The gross realized gain or loss, net, for fixed maturities included in earnings for the period.

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This item represents the gross profit realized on the sale of equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross profit realized on the sale of fixed maturities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of fixed maturities categorized neither as held-to-maturity nor trading securities.

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The amount charged to income if the decline in fair value for equity securities is deemed to be other than temporary.

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The amount charged to income if the decline in fair value for fixed maturities is deemed to be other than temporary.

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This item represents the gross realized gain (loss) included in earnings for the period as a result of selling or holding other invested assets.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References

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

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