Fair Value of Assets and Liabilities (Details 4) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair value assets measured on recurring basis, change in unrealized gain (loss) included in earnings	$ (23)	$ (2)	$ 10
Gains (losses) for Level 3 liabilities still held at the balance sheet date, included in earnings	5	19	9
Gains (losses) for Level 3 assets and liabilities still held at the balance sheet date, included in earnings	(18)	17	19
Realized capital gains and losses
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date	(36)	(20)	(3)
Net investment income
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date	13	18	12
Interest credited to contractholder funds
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date	(4)	26	(5)
Life and annuity contract benefits
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date	9	(7)	15
Contractholder funds: Derivatives embedded in life and annuity contracts
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 liabilities still held at the balance sheet date, included in earnings	5	19	(8)
Liabilities held for sale
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 liabilities still held at the balance sheet date, included in earnings	0	0	17
Fixed income securities
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair value assets measured on recurring basis, change in unrealized gain (loss) included in earnings	4	1	4
Municipal
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair value assets measured on recurring basis, change in unrealized gain (loss) included in earnings	2	(12)	(7)
Corporate
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair value assets measured on recurring basis, change in unrealized gain (loss) included in earnings	2	11	11
ABS
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair value assets measured on recurring basis, change in unrealized gain (loss) included in earnings	0	2	1
RMBS
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair value assets measured on recurring basis, change in unrealized gain (loss) included in earnings	0	0	(1)
Equity securities
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair value assets measured on recurring basis, change in unrealized gain (loss) included in earnings	(32)	(4)	0
Free-standing derivatives, net
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair value assets measured on recurring basis, change in unrealized gain (loss) included in earnings	5	1	5
Other assets
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair value assets measured on recurring basis, change in unrealized gain (loss) included in earnings	$ 0	$ 0	$ 1

This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets). Such unrealized (holding) gains or losses relate to those assets and liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets). Such unrealized (holding) gains or losses relate to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

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- Definition

Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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