Investments (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Net Investment Income:
Investment income, before expense	$ 867	$ 1,001	$ 2,798	$ 3,070
Investment expense	(44)	(51)	(118)	(153)
Net investment income	823	950	2,680	2,917
Fixed income securities
Net Investment Income:
Investment income, before expense	581	721	1,870	2,223
Equity securities
Net Investment Income:
Investment income, before expense	28	30	91	94
Mortgage loans
Net Investment Income:
Investment income, before expense	54	99	206	290
Limited partnership interests
Net Investment Income:
Investment income, before expense	162	106	499	339
Short-term investments
Net Investment Income:
Investment income, before expense	1	1	5	4
Other
Net Investment Income:
Investment income, before expense	$ 41	$ 44	$ 127	$ 120