Investments (Repurchase Agreement - Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Offsetting Assets [Line Items]
Fair Value of Securities Received as Collateral that Have Been Resold or Repledged	$ 114
Receivable Under Reverse Repurchase Agreements	300
Payable Under Repurchase Agreements	300
Amount Offset in Balance Sheet	300
Maximum
Offsetting Assets [Line Items]
Net Amount Assets (Liabilities) From Repurchase, Reverse Repurchase Agreements	1
Corporate fixed maturity securities
Offsetting Assets [Line Items]
Payable Under Repurchase Agreements	$ 300
Fixed Maturity Securities
Offsetting Assets [Line Items]
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	$ 316	$ 0
Securities Borrowed, Not Subject to Master Netting Arrangement	$ 306	$ 0
Fixed Maturity Securities \| Minimum
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 Securities Loaned at Inception Based on Cash Collateral Received	85.00%
Fixed Maturity Securities \| Maximum
Offsetting Assets [Line Items]
Percentage of Estimated Fair Value of Securities Loaned at Inception Based on Cash Collateral Received	100.00%

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

No definition available.

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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

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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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=64858031&loc=SL6224234-111729

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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.

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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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- Definition

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

+ References

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