Investments (Details 6) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses	$ (207)	$ (239)	$ (563)
Portion of loss recognized in other comprehensive income	(8)	6	(33)
Net other-than-temporary impairment losses recognized in earnings	(215)	(233)	(596)
Fixed income securities
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses	(59)	(150)	(361)
Portion of loss recognized in other comprehensive income	(8)	6	(33)
Net other-than-temporary impairment losses recognized in earnings	(67)	(144)	(394)
Municipal
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses	(24)	(42)	(59)
Portion of loss recognized in other comprehensive income	(5)	9	(3)
Net other-than-temporary impairment losses recognized in earnings	(29)	(33)	(62)
Corporate
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses		(21)	(30)
Portion of loss recognized in other comprehensive income		(2)	6
Net other-than-temporary impairment losses recognized in earnings		(23)	(24)
Foreign government
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses			(1)
Net other-than-temporary impairment losses recognized in earnings			(1)
Asset-backed securities ("ABS")
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses			(9)
Portion of loss recognized in other comprehensive income	(2)		2
Net other-than-temporary impairment losses recognized in earnings	(2)		(7)
Residential mortgage-backed securities ("RMBS")
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses	(3)	(65)	(196)
Portion of loss recognized in other comprehensive income	2	(4)	(39)
Net other-than-temporary impairment losses recognized in earnings	(1)	(69)	(235)
Commercial mortgage-backed securities ("CMBS")
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses	(32)	(22)	(66)
Portion of loss recognized in other comprehensive income	(3)	3	1
Net other-than-temporary impairment losses recognized in earnings	(35)	(19)	(65)
Equity securities
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses	(137)	(75)	(139)
Net other-than-temporary impairment losses recognized in earnings	(137)	(75)	(139)
Mortgage loans
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses	11	5	(37)
Net other-than-temporary impairment losses recognized in earnings	11	5	(37)
Limited partnership interests
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses	(18)	(8)	(6)
Net other-than-temporary impairment losses recognized in earnings	(18)	(8)	(6)
Other
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment losses	(4)	(11)	(20)
Net other-than-temporary impairment losses recognized in earnings	$ (4)	$ (11)	$ (20)