Investments (Details 26) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
The Components of Net Investment Income
Fixed maturity securities	$ 3,737	$ 3,791	$ 7,545	$ 7,474
Equity securities	38	48	70	78
Trading securities - actively traded and FVO general account securities	(1)	16	44	44
Mortgage loans	764	766	1,594	1,525
Policy loans	156	160	314	320
Real estate and real estate joint ventures	280	187	457	333
Other limited partnership interests	266	159	448	402
Cash, cash equivalents and short-term investments	39	44	75	90
International joint ventures	1	7	4	(14)
Other	80	101	121	69
Subtotal	5,360	5,279	10,672	10,321
Less: Investment expenses	258	249	517	494
Subtotal, net	5,102	5,030	10,155	9,827
Trading securities - FVO contractholder-directed unit-linked investments	(517)	(32)	498	387
Securitized reverse residential mortgage loan	89	0	174	0
FVO consolidated securitization entities:
Commercial mortgage loans	44	96	89	191
Securities	1	0	3	1
Subtotal	(383)	64	764	579
Net investment income	4,719	5,094	10,919	10,406
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	(5)	0	24	21
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	$ (378)	$ (84)	$ 499	$ 232

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Securitized reverse residential mortgage loan.

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