Investments (Details 2) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
The credit portion of other-than-temporary impairments on fixed maturity securities, non-credit portion of an impairment has been recognized in other comprehensive income (loss)
Beginning Balance	$ 171	$ 121	$ 143	$ 99
Additional credit impairments on:
Previously impaired securities	8	11	37	34
Securities without prior impairments	2	1	7	8
Reductions - disposals	(1)		(7)	(8)
Ending Balance	$ 180	$ 133	$ 180	$ 133

Additional credit impairments on securities and Its adjustments.

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The credit portion of other-than-temporary impairments on fixed maturity securities, non-credit portion of an impairment has been recognized in other comprehensive income (loss).

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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

+ References

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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which no such other than temporary impairment (OTTI) was previously recognized.

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The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

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This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because of the sale of impaired securities during the period.

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