Investments (Details 5) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Investments
Impairment write-downs	$ (33)	$ (49)	$ (43)	$ (88)
Change in intent write-downs	(27)	(1)	(54)	(45)
Net other-than-temporary impairment losses recognized in earnings	(60)	(50)	(97)	(133)
Sales	408	70	580	299
Valuation of derivative instruments	3	(10)	(1)	1
Settlements of derivative instruments	11	17	11	28
Total realized capital gains and losses	362	27	493	195
Fixed income securities
Investments
Net other-than-temporary impairment losses recognized in earnings	(11)	(27)	(53)	(91)
Total realized capital gains and losses	79	6	151	(23)
Schedule of Available for Sale Securities
Gross gains on sales of fixed income securities	114	72	248	187
Gross loss on sales of fixed income securities	$ 24	$ 47	$ 44	$ 137