Contingencies and Other Matters - Financial Guarantees (Details) $ in Millions	9 Months Ended
Sep. 30, 2015 USD ($)
Market Value Guarantee [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	$ 41
Guarantee Obligations, Current Carrying Value	11
Market Value Guarantee [Member] \| Expiring In 2016 [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	16
Market Value Guarantee [Member] \| Expiring In 2022 [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	25
Indemnification Guarantee [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	199
Guarantee Obligations, Current Carrying Value	0
Guarantee Type, Other [Member] \| Retirement And Life Insurance Contracts [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Current Carrying Value	$ 496
Separate Accounts Liability Sold Business Percent Reinsured	14.00%
Guarantee Type, Other [Member] \| Variable Annuity [Member] \| Guaranteed Minimum Income Benefit [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	$ 833
Annuitization election period	30 days
Underlying mutual fund investment values for Guaranteed Minimum Income Benefits	$ 940

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

No definition available.

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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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Period Type:	instant

- 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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- Definition

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.

+ Details

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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.

+ 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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- Details

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- Details

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- Details

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- Details

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- Details

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