Investments (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Realized capital gains and losses by asset type
Realized capital gains and losses	$ 294	$ (41)	$ 588	$ 452
Fixed income securities
Realized capital gains and losses by asset type
Realized capital gains and losses	23	24	121	175
Equity securities
Realized capital gains and losses by asset type
Realized capital gains and losses	213	(51)	474	261
Mortgage loans
Realized capital gains and losses by asset type
Realized capital gains and losses	2	(6)	3	19
Limited partnership interests
Realized capital gains and losses by asset type
Realized capital gains and losses	59	2	10	(1)
Derivatives
Realized capital gains and losses by asset type
Realized capital gains and losses	(8)	(12)	(27)	(2)
Other
Realized capital gains and losses by asset type
Realized capital gains and losses	$ 5	$ 2	$ 7