Investments (Consolidated Variable Interest Entities - Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Variable Interest Entity [Line Items]
Tax credits guaranteed by third parties that reduce maximum exposure to loss related to other invested assets	$ 188		$ 188		$ 212
Financial or other support to investees designated as VIEs			0	$ 0
Consolidated Entities
Variable Interest Entity [Line Items]
Variable interest, maximum exposure to loss in consolidated securitization entities	126		$ 126		$ 123
Long-term debt held by consolidated securitization entities, percentage range minimum			2.25%	2.25%
Long-term debt held by consolidated securitization entities, percentage range maximum			5.57%	5.57%
Interest expense on long-term debt held by consolidated securitization entities	$ 8	$ 3	$ 10	$ 34