Investments- Realized Capital Gains and Losses by Transaction Type (Details 5) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Investments [Abstract]
Impairment write-downs	$ (5)	$ 0	$ (12)	$ (4)
Change in intent write-downs	(4)	(14)	(7)	(19)
Net OTTI losses recognized in earnings	(9)	(14)	(19)	(23)
Sales	69	1	186	8
Valuation and settlements of derivative instruments	(1)	3	3	5
Total realized capital gains and losses	59	(10)	170	(10)
Fixed income securities
Investments [Abstract]
Net OTTI losses recognized in earnings	(3)	2	(6)	0
Total realized capital gains and losses	46	5	114	0
Schedule of Available for Sale Securities
Gross gains on sales of fixed income securities	85	36	216	53
Gross losses on sales of fixed income securities	$ 15	$ 15	$ 38	$ 29