Investments (Details 6) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	$ (47)	$ (77)	$ (109)	$ (168)
Included in OCI	(3)	(2)	0	8
Net OTTI losses recognized in earnings	(50)	(79)	(109)	(160)
Fixed income securities
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(4)	(1)	(20)	(27)
Included in OCI	(3)	(2)	0	8
Net OTTI losses recognized in earnings	(7)	(3)	(20)	(19)
Municipal
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(1)	0	(1)	0
Included in OCI	(2)	0	(2)	0
Net OTTI losses recognized in earnings	(3)	0	(3)	0
Corporate
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	0	(1)	(9)	(17)
Included in OCI	0	0	3	7
Net OTTI losses recognized in earnings	0	(1)	(6)	(10)
Asset-backed securities (“ABS”)
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(1)	0	(1)	(6)
Included in OCI	0	(1)	0	0
Net OTTI losses recognized in earnings	(1)	(1)	(1)	(6)
Residential mortgage-backed securities (“RMBS”)
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses			(1)	0
Included in OCI			(3)	0
Net OTTI losses recognized in earnings			(4)	0
Commercial mortgage-backed securities (“CMBS”)
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(2)	0	(8)	(4)
Included in OCI	(1)	(1)	2	1
Net OTTI losses recognized in earnings	(3)	(1)	(6)	(3)
Equity securities
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(32)	(51)	(68)	(128)
Included in OCI	0	0	0	0
Net OTTI losses recognized in earnings	(32)	(51)	(68)	(128)
Limited partnership interests
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(9)	(24)	(16)	(11)
Included in OCI	0	0	0	0
Net OTTI losses recognized in earnings	(9)	(24)	(16)	(11)
Other
Other-than-temporary impairment losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(2)	(1)	(5)	(2)
Included in OCI	0	0	0	0
Net OTTI losses recognized in earnings	$ (2)	$ (1)	$ (5)	$ (2)