Investments - Impairments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Impairments Table Details [Abstract]
Credit-related	$ 0	[1]	$ 0	[1]	$ (8)	[1]	$ (14)	[1]
Other	(3)		0		(11)		(2)
Total	$ (3)		$ 0		$ (19)		$ (16)

[1] Credit related losses include other-than-temporary declines in fair value of fixed maturities and changes in valuation reserves and asset write-downs related to commercial mortgage loans and real estate entities. There were no credit losses on fixed maturities for which a portion of the impairment was recognized in other comprehensive income.