Investments (Details 6) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	$ (26)	$ (73)	$ (135)	$ (241)
Included in OCI	(2)	0	(2)	8
Net OTTI losses recognized in earnings	(28)	(73)	(137)	(233)
Municipal
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses			(1)	0
Included in OCI			(2)	0
Net OTTI losses recognized in earnings			(3)	0
Corporate
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	0	(13)	(9)	(30)
Included in OCI	0	0	3	7
Net OTTI losses recognized in earnings	0	(13)	(6)	(23)
Asset-backed securities (“ABS”)
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	0	0	(1)	(6)
Included in OCI	(1)	0	(1)	0
Net OTTI losses recognized in earnings	(1)	0	(2)	(6)
Residential mortgage-backed securities (“RMBS”)
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	0	(1)	(1)	(1)
Included in OCI	0	0	(3)	0
Net OTTI losses recognized in earnings	0	(1)	(4)	(1)
Fixed income securities
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(1)	(17)	(21)	(44)
Included in OCI	(2)	0	(2)	8
Net OTTI losses recognized in earnings	(3)	(17)	(23)	(36)
Equity securities
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(8)	(27)	(77)	(155)
Included in OCI	0	0	0	0
Net OTTI losses recognized in earnings	(8)	(27)	(77)	(155)
Mortgage loans
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(1)	0	(1)	0
Included in OCI	0	0	0	0
Net OTTI losses recognized in earnings	(1)	0	(1)	0
Limited partnership interests
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(16)	(22)	(32)	(33)
Included in OCI	0	0	0	0
Net OTTI losses recognized in earnings	(16)	(22)	(32)	(33)
Other
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	0	(7)	(4)	(9)
Included in OCI	0	0	0	0
Net OTTI losses recognized in earnings	0	(7)	(4)	(9)
Commercial mortgage-backed securities (“CMBS”)
Realized capital gains and losses by asset type
Total other-than-temporary impairment (“OTTI”) losses	(1)	(3)	(9)	(7)
Included in OCI	(1)	0	1	1
Net OTTI losses recognized in earnings	$ (2)	$ (3)	$ (8)	$ (6)

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Amount before tax of other than temporary impairment loss (OTTI) on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss and attributable to parent entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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