Investments (Details 14) (USD $) In Millions	9 Months Ended	12 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Changes in fixed maturity securities with noncredit OTTI losses in accumulated other comprehensive income (loss)
Balance, beginning of period	$ (601)	$ (859)
Noncredit OTTI losses recognized	5	(212)
Transferred to retained earnings	0	16
Securities sold with a previous noncredit OTTI loss	99	137
Subsequent increases in estimated fair value	(181)	317
Balance, end of period	$ (678)	$ (601)

Pre tax reclassification adjustment for gains or losses realized upon the sale of securities.

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+ Details