Investments (details) - Impairment Charges (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Impairment charges
Impairment charges	$ 10	$ 3	$ 20	$ 10
Fixed maturities [Member]
Impairment charges
Impairment charges	9		13	2
Mortgage-backed securities, collateralized mortgage obligations and pass-through securities [Member]
Impairment charges
Impairment charges			1	2
All other corporate bonds [Member]
Impairment charges
Impairment charges	9		12
Equity securities [Member]
Impairment charges
Impairment charges	1	2	6	3
Equity securities, public common stock [Member]
Impairment charges
Impairment charges	1	2	6	3
Other investments [Member]
Impairment charges
Impairment charges		$ 1	$ 1	$ 5