Investments (Details 21) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Total OTTI losses recognized in earnings:
Net investment gains (losses)	$ (149)	$ (127)
Total gains (losses) on fixed maturity securities:
Other-than-temporary impairments on fixed maturity securities	(135)	(132)
Other-than-temporary impairments on fixed maturity securities transferred to other comprehensive income (loss)	2	9
Total OTTI losses recognized in earnings	(133)	(123)
Fixed maturity securities - net gains (losses) on sales and disposals	(7)	(40)
Other net investment gains (losses):
Trading and other securities FVO general account securities - changes in estimated fair value	4	0
Mortgage Loans	36	47
Real estate and real estate joint ventures	(4)	1
Other limited partnership interests	(2)	3
Other investment portfolio gains (losses)	(25)	4
Subtotal - investment portfolio gains (losses)	(140)	(72)
FVO consolidated securitization entities - changes in estimated fair value included in net investment gains (losses):
Commercial mortgage loans	6	18
Trading securities	0	(40)
Long-term debt - related to trading securities	(11)	47
Other Gains Losses	35	(52)
Subtotal consolidated securitizations entities and other gains (losses)	30	(27)
Total net investment gains (losses)	(110)	(99)
Fixed maturity securities [Member]
Total OTTI losses recognized in earnings:
Net investment gains (losses)	(140)	(163)
Total gains (losses) on fixed maturity securities:
Total OTTI losses recognized in earnings	(133)	(123)
Equity Securities [Member]
Total OTTI losses recognized in earnings:
Net investment gains (losses)	$ (9)	$ 36

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