Investments and Derivative Instruments (Details 18) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Total	$ (134)		$ 1,206		$ (854)		$ 650
Interest rate swaps, swap options , caps, floors and forwards [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	(4)		9		(6)		16
Foreign currency swaps and forwards [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	(1)		11		12		4
Japan 3Win Related Foreign Currency Swaps [Member] | JAPAN
Derivative Instruments, Gain (Loss) [Line Items]
Total	15	[1]	39	[1]	(106)	[1]	14	[1]
Fixed annuity hedging instruments [Member] | JAPAN
Derivative Instruments, Gain (Loss) [Line Items]
Total	24	[2]	103	[2]	(46)	[2]	98	[2]
Credit Derivatives that Purchase Credit Protection [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	4		18		(15)		5
Credit Derivatives that Assume Credit Risk [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	61		(146)		194		(143)
Equity index swaps and options [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	(9)		(40)		(22)		(38)
GMWB product derivatives [Member] | U.S. [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	823		(1,315)		1,235		(1,047)
GMWB Reinsurance [Member] | U.S. [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	(184)		241		(265)		180
GMWB hedging instruments [Member] | U.S. [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	(258)		751		(519)		567
Macro Hedge Program [Member] | U.S. [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	(109)		107		(292)		6
International program product derivatives [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	5		(32)		13		(27)
International program hedging instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	(117)		1,142		(472)		857
GMAB, GMWB, and GMIB Reinsurance Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	348		(548)		599		(212)
Coinsurance and Modified Coinsurance Reinsurance Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	$ (732)		$ 866		$ (1,164)		$ 370

[1] The associated liability is adjusted for changes in spot rates through realized capital gains and was $(46) and $(93) for the three months ended September 30, 2012 and 2011, respectively, and $19 and $(100) for the nine months ended September 30, 2012 and 2011, respectively.

[2] The associated liability is adjusted for changes in spot rates through realized capital gains and was $(54) and $(115) for the three months ended September 30, 2012 and 2011, respectively and $33 and $(125) for the nine months ended September 30, 2012 and 2011, respectively.