Investments and Derivative Instruments (Non-qualifying Strategies) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Derivative Instruments Gain (Loss) [Line Items]
Total	$ (1,922)		$ 20		$ (78)
Interest rate swaps, caps, floors and forwards [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	26		20		14
Foreign currency swaps and forwards [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	10		1		(3)
3 Win Related Foreign Currency Swaps [Member] | JAPAN [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	(300)	[1]	31	[1]	215	[1]
Fixed annuity hedging instruments [Member] | JAPAN [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	(178)	[2]	109	[2]	385	[2]
Credit Derivatives that Purchase Credit Protection [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	(19)		(8)		(17)
Credit Derivatives that Assume Credit Risk [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	204		(141)		157
Equity index swaps and options [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	(31)		(67)		5
GMWB product derivatives [Member] | U.S. [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	1,430		(780)		486
GMWB Reinsurance [Member] | U.S. [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	(280)		131		(102)
GMWB hedging instruments [Member] | U.S. [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	(631)		252		(295)
Macro Hedge Program [Member] | U.S. [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	(340)		(216)		(445)
International program product derivatives [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	0		0		0
International program hedging instruments [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	(1,145)		639		(1)
GMAB, GMWB, and GMIB Reinsurance Contracts [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	1,233		(326)		(769)
Coinsurance and Modified Coinsurance Reinsurance Contracts [Member]
Derivative Instruments Gain (Loss) [Line Items]
Total	$ (1,901)		$ 375		$ 292

[1] The associated liability is adjusted for changes in spot rates through realized capital gains and was $189, $(100) and $(273) for the years ended December 31, 2012, 2011 and 2010, respectively.

[2] The associated liability is adjusted for changes in spot rates through realized capital gains and losses and was $245, $(129) and $(332) for the years ended December 31, 2012, 2011, and 2010, respectively.