Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

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Amount of equity securities categorized neither as held-to-maturity nor as trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
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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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-Section 45
-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 2
-Subparagraph (a)
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For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Fair Value Measurements Level 4 Fair Value Option (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Fair Value, Option, Quantitative Disclosures [Line Items]
Available-for-sale Securities, Equity Securities	$ 875		$ 875		$ 1,121
Available-for-sale Equity Securities, Amortized Cost Basis	812		812		1,135
Fair Value of Assets Accounted for Using Fair Value Option	180,260		180,260		181,633
Fair Value, Option, Changes in Fair Value, Gain (Loss)	4	$ (4)	(26)	$ (4)
Corporate Debt Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Option, Changes in Fair Value, Gain (Loss)	1	(2)	1	(5)
Collateralized Debt Obligations [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Option, Changes in Fair Value, Gain (Loss)	0	1	0	2
Foreign Government Debt Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Option, Changes in Fair Value, Gain (Loss)	0	(3)	(1)	(4)
Residential Mortgage Backed Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Option, Changes in Fair Value, Gain (Loss)	3	0	8	0
Fixed Maturities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Option, Changes in Fair Value, Gain (Loss)	4	(4)	8	(7)
Equity Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Available-for-sale Securities, Equity Securities	0		0		282
Available-for-sale Equity Securities, Amortized Cost Basis	0		0		293
Fair Value, Option, Changes in Fair Value, Gain (Loss)	0	$ 0	(34)	$ 3
Equity Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value of Assets Accounted for Using Fair Value Option	0		0		282
Fixed Maturities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value of Assets Accounted for Using Fair Value Option	360		360		503
Fixed Maturities [Member] \| Asset-backed Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value of Assets Accounted for Using Fair Value Option	6		6		13
Fixed Maturities [Member] \| Corporate Debt Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value of Assets Accounted for Using Fair Value Option	34		34		87
Fixed Maturities [Member] \| Collateralized Debt Obligations [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value of Assets Accounted for Using Fair Value Option	3		3		6
Fixed Maturities [Member] \| Commercial Mortgage Backed Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value of Assets Accounted for Using Fair Value Option	8		8		24
Fixed Maturities [Member] \| Foreign Government Debt Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value of Assets Accounted for Using Fair Value Option	0		0		2
Fixed Maturities [Member] \| Residential Mortgage Backed Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value of Assets Accounted for Using Fair Value Option	307		307		368
Fixed Maturities [Member] \| US Treasury Bond Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value of Assets Accounted for Using Fair Value Option	$ 2		$ 2		$ 3