Investments (Details 26) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
The Components of Net Investment Income
Fixed maturity securities	$ 3,770	$ 3,060	$ 11,244	$ 9,126
Equity securities	28	19	106	83
Trading securities - actively traded and FVO general account securities	(38)	45	6	56
Mortgage loans	806	713	2,331	2,081
Policy loans	162	155	482	488
Real estate and real estate joint ventures	213	131	557	300
Other limited partnership interests	180	170	582	596
Cash, cash equivalents and short-term investments	41	26	131	64
International joint ventures	7	19	(3)	(61)
Other	82	(7)	151	181
Subtotal	5,251	4,331	15,587	12,914
Less: Investment expenses	271	222	774	654
Subtotal, net	4,980	4,109	14,813	12,260
Trading securities - FVO contractholder-directed unit-linked investments	(824)	149	(437)	161
FVO consolidated securitization entities:
Commercial mortgage loans	95	102	286	312
Securities	6	4	7	12
Subtotal	(723)	255	(144)	485
Net investment income	4,257	4,364	14,669	12,745
Actively traded securities and FVO general account securities [Member]
Changes in estimated fair value subsequent to purchase included in net investment income:
Changes in estimated fair value included in net investment income	(46)	29	(25)	16
FVO contractholder-directed unit-linked investments [Member]
Changes in estimated fair value subsequent to purchase included in net investment income:
Changes in estimated fair value included in net investment income	$ (873)	$ 124	$ (641)	$ 111

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