Fair Value of Assets and Liabilities (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
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	$ (278)	$ (247)
Weighted average projected option cost (as a percent)	1.76%	1.75%
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)	2.00%	2.00%
Liabilities held for sale - Equity-indexed and forward starting options \| Stochastic cash flow model
Quantitative information about the significant unobservable inputs
Fair value		(246)
Weighted average projected option cost (as a percent)		1.91%
Liabilities held for sale - 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%
Liabilities held for sale - Equity-indexed and forward starting options \| Maximum \| Stochastic cash flow model
Quantitative information about the significant unobservable inputs
Projected option cost (as a percent)		2.00%
Fixed income securities - non-binding broker quotes
Quantitative information about the significant unobservable inputs
Fair value	1,030	1,270
Fair value		319
Municipal - not rated by third party credit rating agencies
Quantitative information about the significant unobservable inputs
Fair value	$ 169	$ 208

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

No definition available.

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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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- Definition

Fair value portion of assets classified as held for sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19190-110258

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