Fair Value of Assets and Liabilities (Details 2) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Derivatives embedded in life and annuity contracts - Equity-indexed and forward starting options \| Stochastic cash flow model
Quantitative information about the significant unobservable inputs
Fair value	$ (270)	$ (278)
Weighted average projected option cost (as a percent)	1.76%	1.76%
Derivatives embedded in life and annuity contracts - Equity-indexed and forward starting options \| Minimum \| Stochastic cash flow model
Quantitative information about the significant unobservable inputs
Projected option cost (as a percent)	1.00%	1.00%
Derivatives embedded in life and annuity contracts - Equity-indexed and forward starting options \| Maximum \| Stochastic cash flow model
Quantitative information about the significant unobservable inputs
Projected option cost (as a percent)	2.20%	2.00%
Fixed income securities - non-binding broker quotes
Quantitative information about the significant unobservable inputs
Fair value	$ 719	$ 1,030
Municipal - not rated by third party credit rating agencies
Quantitative information about the significant unobservable inputs
Fair value	$ 121	$ 169

Represents the percentage of projected option cost as an input to measure fair value.

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- Definition

Represents the weighted average percentage of projected option cost as an input to measure fair value.

+ References

No definition available.

+ Details

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- Definition

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

+ 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 (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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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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