Investments and Derivative Instruments (Details 16) (Cash Flow Hedging [Member], USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012	Jun. 30, 2013		Jun. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	$ (79)		$ 75	$ (120)		$ 44
Net Realized Capital Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	(2)		0	(2)		0
Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)	18		16	93		47
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	(84)		89	(126)		61
Net Realized Capital Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	(2)		0	(2)		0
Interest Rate Swap [Member] | Net realized capital gains (losses) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)	2	[1]	0	66	[1]	4
Interest Rate Swap [Member] | Interest Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)	15		26	29		51
Foreign Currency Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	5		(14)	6		(17)
Net Realized Capital Gains (Losses) Recognized in Income on Derivative (Ineffective Portion)	0		0	0		0
Foreign Currency Swap [Member] | Net realized capital gains (losses) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)	$ 1		$ (10)	$ (2)		$ (8)

[1] Includes $71 of net gains on cash flow hedging instruments relating to the sales of the Retirement Plans and Individual Life businesses.