Derivative Financial Instruments (Details 2) (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 Financial Instruments
Cash flow hedge losses to be reclassified from AOCI during the next twelve months	$ (1)		$ (1)
Effective portion
(Loss) gain recognized in OCI on derivatives during the period	(3)	20	(3)	7
Loss recognized in OCI on derivatives during the term of the hedging relationship	(14)	(10)	(14)	(10)
Loss reclassified from AOCI into income (net investment income)		(1)
Loss reclassified from AOCI into income (realized capital gains and losses)			(1)
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives		(1)	(1)	(47)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	184	(224)	266	(162)
Total gain (loss) recognized in net income on derivatives	184	(225)	265	(209)
Net investment income
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives		(1)	(1)	(2)
Total gain (loss) recognized in net income on derivatives		(1)	(1)	(2)
Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives				(8)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	8	(186)	35	(199)
Total gain (loss) recognized in net income on derivatives	8	(186)	35	(207)
Contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	18	(55)	32	(18)
Total gain (loss) recognized in net income on derivatives	18	(55)	32	(18)
Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives				(37)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	158	17	199	55
Total gain (loss) recognized in net income on derivatives	158	17	199	18
Interest rate contracts
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives		(1)	(1)	(15)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(1)	(130)	2	(152)
Interest rate contracts | Net investment income
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives		(1)	(1)	(2)
Interest rate contracts | Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives				(8)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(1)	(130)	2	(152)
Interest rate contracts | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives				(5)
Equity and index contracts
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	19	(71)	56	(25)
Equity and index contracts | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	19	(71)	56	(25)
Embedded derivative financial instruments
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	158	(17)	192	3
Embedded derivative financial instruments | Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	2	(49)	20	(53)
Embedded derivative financial instruments | Contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	18	(55)	32	(18)
Embedded derivative financial instruments | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	138	87	140	74
Foreign currency contracts
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives			(1)
Foreign currency contracts | Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives			(1)
Credit default swaps
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	7	(7)	14	6
Credit default swaps | Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	7	(7)	14	6
Other contracts
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	1	1	3	6
Other contracts | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	1	1	3	6
Foreign currency and interest rate contracts
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives				(32)
Foreign currency and interest rate contracts | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives				$ (32)