Derivative Financial Instruments (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Derivative Financial Instruments
Cash flow hedge losses to be reclassified from AOCI during the next twelve months	$ 1		$ 1
Effective portion
Gain (loss) recognized in OCI on derivatives during the period	5	(5)		(13)
Loss recognized in OCI on derivatives during the term of the hedging relationship	(16)	(36)	(16)	(36)
Ineffective portion and amount excluded from effectiveness
Gain reclassified from AOCI into income (net investment income)		1		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		(2)	(1)	(46)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	9	(41)	95	(28)
Total gain (loss) recognized in net income on derivatives	9	(43)	94	(74)
Net investment income
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives		(2)	(1)	(1)
Total gain (loss) recognized in net income on derivatives		(2)	(1)	(1)
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	7	(53)	29	(112)
Total gain (loss) recognized in net income on derivatives	7	(53)	29	(120)
Life and annuity contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(17)	(8)	14	37
Total gain (loss) recognized in net income on derivatives	(17)	(8)	14	37
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	24	20	41	38
Total gain (loss) recognized in net income on derivatives	24	20	41	1
Operating costs and expenses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(5)		11	9
Total gain (loss) recognized in net income on derivatives	(5)		11	9
Interest rate contracts
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives		(2)	(1)	(14)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	2	(53)	1	(104)
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		(2)	(1)	(1)
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	2	(53)	1	(104)
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	(16)	8	47	34
Equity and index 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	4		1	(19)
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	(16)	8	37	46
Equity and index contracts | Operating costs and expenses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(4)		9	7
Embedded derivative financial instruments
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	27	(2)	35	29
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	4	(3)	19	5
Embedded derivative financial instruments | Life and annuity contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(17)	(8)	14	37
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	40	9	2	(13)
Foreign currency contracts
Derivative Instruments, Gain (Loss)
Derivatives in fair value accounting hedging relationships, total gain (loss) recognized in net income on derivatives				(32)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(4)		2	(3)
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	(3)			(5)
Foreign currency 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)
Foreign currency contracts | Operating costs and expenses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(1)		2	2
Credit default swaps
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives		3	8	11
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		3	8	11
Other contracts
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives		3	2	5
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		$ 3	$ 2	$ 5