Contingencies and Other Matters - Financial Guarantees (Details) (USD $)	12 Months Ended
Dec. 31, 2014
Market Value Guarantee [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	$ 41,000,000
Guarantee Obligations, Current Carrying Value	7,000,000
Market Value Guarantee [Member] \| Expiring In 2016 [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	16,000,000
Market Value Guarantee [Member] \| Expiring In 2025 [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	25,000,000
Indemnification Guarantee [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	208,000,000
Guarantee Obligations, Current Carrying Value	0
Guarantee Type, Other [Member] \| Retirement And Life Insurance Contracts [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	496,000,000
Guarantee Obligations, Current Carrying Value	0
Separate Accounts Liability Sold Business Percent Reinsured	13.00%
Guarantee Type, Other [Member] \| Retirement And Life Insurance Contracts [Member] \| Guaranteed Minimum Income Benefit [Member]
Guarantee Obligations [Line Items]
Annuitization election period	30 days
Maximum potential undiscounted payments under Guaranteed Minimum Income Benefits assumptions	754,000,000
Underlying mutual fund investment values for Guaranteed Minimum Income Benefits	$ 1,100,000,000

The period of time prior to a policy anniversary when an annuitization election must occur.

No definition available.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions for the Guaranteed Minimum Income Benefits business under hypothetical defined assumptions

+ References

No definition available.

+ Details

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- Definition

The percentage of separate account assets associated with the sold retirement benefits business that represent the fair value of contract holder funds guaranteed by the Company.

+ References

No definition available.

+ Details

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- Definition

The value of investments in mutual funds assumed in calculating the reporting entity's maximum potential future payments for guarantees related to reinsured benefits.

+ References

No definition available.

+ Details

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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- Details

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- Definition

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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- Details

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- Details

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- Details

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