DAC, VOBA, DSI, and DFEL (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Changes in DAC [Roll Forward]
Balance as of beginning-of-year	$ 5,721	$ 6,036	$ 7,424
Cumulative Effect Of Change In Accounting Principle Dac Adjustment Amount	0	0	(1,578)
Deferrals	1,294	1,375	1,357
Amortization, net of interest:
Unlocking	(71)	(130)	92
Other amortization	(785)	(687)	(690)
Adjustment related to realized (gains) losses	(70)	(18)	(42)
Adjustment related to unrealized (gains) losses	(146)	(855)	(527)
Balance as of end-of-year	5,943	5,721	6,036
Changes in VOBA [Roll Forward]
Balance as of beginning-of-year	1,055	1,378	2,086
Business acquired (sold) through reinsurance	2	12	0
Deferrals	12	20	26
Amortization:
Unlocking	(23)	174	(47)
Other amortization	(225)	(279)	(351)
Accretion of interest	73	78	89
Adjustment related to realized (gains) losses	9	(6)	(8)
Adjustment related to unrealized (gains) losses	(179)	(322)	(417)
Balance as of end-of-year	724	1,055	1,378
Interest accrual rate, low end	3.30%
Interest accrual rate, high end	7.05%
Estimated future amortization of VOBA, net of interest [Abstract]
2013	94
2014	72
2015	64
2016	57
2017	52
Changes in DSI [Roll Forward]
Balance as of beginning-of-year	271	286	323
Deferrals	39	39	66
Amortization, net of interest:
Unlocking	14	(2)	(3)
Other amortization	(46)	(38)	(51)
Adjustment related to realized (gains) losses	(8)	(1)	(8)
Adjustment related to unrealized (gains) losses	(17)	(13)	(41)
Balance as of end-of-year	253	271	286
Changes in DFEL [Abstract]
Balance as of beginning-of-year	1,369	1,502	1,338
Deferrals	349	544	546
Amortization, net of interest:
Unlocking	(69)	31	(1)
Other amortization	(216)	(166)	(196)
Adjustment related to realized (gains) losses	(18)	(9)	(8)
Adjustment related to unrealized (gains) losses	(42)	(533)	(177)
Balance as of end-of-year	$ 1,373	$ 1,369	$ 1,502