Investments- Realized Capital Gains and Losses (Details 4) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Realized capital gains and losses by asset type
Realized capital gains and losses	$ 59	$ (10)	$ 170	$ (10)
Fixed income securities
Realized capital gains and losses by asset type
Realized capital gains and losses	46	5	114	0
Mortgage loans
Realized capital gains and losses by asset type
Realized capital gains and losses	1	(2)	1	1
Equity securities
Realized capital gains and losses by asset type
Realized capital gains and losses	16	14	48	16
Limited partnership interests
Realized capital gains and losses by asset type
Realized capital gains and losses	(2)	(28)	2	(33)
Derivatives
Realized capital gains and losses by asset type
Realized capital gains and losses	(1)	1	6	3
Other
Realized capital gains and losses by asset type
Realized capital gains and losses	$ (1)	$ 0	$ (1)	$ 3