Investments (Details 6) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	$ (120)	$ (144)	$ (54)
OTTI losses reclassified to (from) other comprehensive income	7	16	(1)
Net OTTI losses recognized in earnings	(113)	(128)	(55)
Fixed income securities
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(42)	(42)	(9)
OTTI losses reclassified to (from) other comprehensive income	7	16	(1)
Net OTTI losses recognized in earnings	(35)	(26)	(10)
Municipal
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	0	0	(1)
OTTI losses reclassified to (from) other comprehensive income	0	0	0
Net OTTI losses recognized in earnings	0	0	(1)
Corporate
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(23)	(25)	(4)
OTTI losses reclassified to (from) other comprehensive income	6	6	0
Net OTTI losses recognized in earnings	(17)	(19)	(4)
ABS
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(4)	(16)	(5)
OTTI losses reclassified to (from) other comprehensive income	0	10	0
Net OTTI losses recognized in earnings	(4)	(6)	(5)
RMBS
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	0	0	2
OTTI losses reclassified to (from) other comprehensive income	(1)	0	(1)
Net OTTI losses recognized in earnings	(1)	0	1
CMBS
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(15)	(1)	(1)
OTTI losses reclassified to (from) other comprehensive income	2	0	0
Net OTTI losses recognized in earnings	(13)	(1)	(1)
Mortgage loans
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	0	4	5
OTTI losses reclassified to (from) other comprehensive income	0	0	0
Net OTTI losses recognized in earnings	0	4	5
Equity securities
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(59)	(83)	(32)
OTTI losses reclassified to (from) other comprehensive income	0	0	0
Net OTTI losses recognized in earnings	(59)	(83)	(32)
Limited partnership interests
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(15)	(17)	(18)
OTTI losses reclassified to (from) other comprehensive income	0	0	0
Net OTTI losses recognized in earnings	(15)	(17)	(18)
Other
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(4)	(6)	0
OTTI losses reclassified to (from) other comprehensive income	0	0	0
Net OTTI losses recognized in earnings	$ (4)	$ (6)	$ 0