Investments (Details 21) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Total OTTI losses recognized in earnings:
Net investment gains (losses)	$ (186)	$ (66)	$ (488)	$ (158)
Total gains (losses) on fixed maturity securities:
Other-than-temporary impairments on fixed maturity securities	(95)	(143)	(525)	(538)
Other-than-temporary impairments on fixed maturity securities transferred to other comprehensive income (loss)	(189)	24	(5)	181
Total OTTI losses recognized in earnings	(284)	(119)	(530)	(357)
Fixed maturity securities - net gains (losses) on sales and disposals	101	54	79	99
Other net investment gains (losses):
Trading and other securities FVO general account securities - changes in estimated fair value	(3)	0	(3)	0
Mortgage Loans	45	37	160	20
Real estate and real estate joint ventures	139	(1)	144	(50)
Other limited partnership interests	0	(4)	8	(15)
Other investment portfolio gains (losses)	0	(67)	(2)	9
Subtotal - investment portfolio gains (losses)	(5)	(101)	(181)	(194)
FVO consolidated securitization entities - changes in estimated fair value included in net investment gains (losses):
Commercial mortgage loans	(64)	114	(39)	767
Trading securities	2	(26)	1	(47)
Long-term debt - related to trading securities	(1)	37	(8)	48
Long-term debt - related to commercial mortgage loans	56	(109)	48	(744)
Other Gains Losses	(43)	(257)	(130)	(154)
Subtotal consolidated securitizations entities and other gains (losses)	(50)	(241)	(128)	(130)
Total net investment gains (losses)	(55)	(342)	(309)	(324)
Fixed maturity securities [Member]
Total OTTI losses recognized in earnings:
Net investment gains (losses)	(183)	(65)	(451)	(258)
Total gains (losses) on fixed maturity securities:
Total OTTI losses recognized in earnings	(284)	(119)	(530)	(357)
Equity Securities [Member]
Total OTTI losses recognized in earnings:
Net investment gains (losses)	$ (3)	$ (1)	$ (37)	$ 100

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