Investments (Repurchase Agreement - Narrative) (Details) $ in Millions	Sep. 30, 2015 USD ($)
Offsetting Assets [Line Items]
Fair Value of Securities Received as Collateral that Have Been Resold or Repledged	$ 227
Receivable Under Reverse Repurchase Agreements	499
Payable Under Repurchase Agreements	449
Amount Offset in Balance Sheet	499
Maximum
Offsetting Assets [Line Items]
Net Amount Assets (Liabilities) From Repurchase, Reverse Repurchase Agreements	$ 1
Fixed Maturity Securities
Offsetting Assets [Line Items]
Percentage of Estimated Fair Value of Securities Loaned at Inception Based on Collateral Obtained	95.00%
Percentage of Estimated Fair Value of Borrowed Securities at Inception Based on Pledged Cash Collateral	98.00%
Securities Loaned, Not Subject to Master Netting Arrangement	$ 524
Securities Borrowed, Not Subject to Master Netting Arrangement	512
Corporate fixed maturity securities
Offsetting Assets [Line Items]
Payable Under Repurchase Agreements	$ 499

Amount offset in balance sheet from receivables and payables under repurchase and reverse repurchase agreement.

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- Definition

Net amount, after affects of netting, from repurchase and reverse repurchase agreements presented on the Balance sheet.

+ References

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- Definition

The gross amounts payable under repurchase agreement.

+ References

No definition available.

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- Definition

The percentage of the estimated fair value of borrowed securities at inception based on pledged cash collateral.

+ References

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- Definition

The percentage of the estimated fair value of securities loaned at inception based on collateral obtained.

+ References

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- Definition

The gross amounts of those recognized receivable under reverse repurchase agreements.

+ References

No definition available.

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- Definition

Fair value of the collateral, or portion thereof, that has been re-pledged, delivered, or otherwise used.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL6224234-111729

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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.

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- Definition

Amount of securities borrowed from entities in exchange for collateral, not subject to a master netting arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 22

-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226052-175313

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Amount of securities loaned to entities in exchange for collateral, not subject to a master netting arrangement.

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