Reinsurance (Components of Reinsurance Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reinsurance receivables related to insurance reserves
Ceded claim and claim adjustment expenses	$ 4,087	$ 4,344	$ 4,972	$ 5,126
Ceded future policy benefits	207	185
Reinsurance receivables related to paid losses	197	213
Reinsurance receivables	4,491	4,742
Allowance for uncollectible reinsurance	(38)	(48)
Reinsurance receivables, net of allowance for uncollectible reinsurance	$ 4,453	$ 4,694

Ceded Claim And Claim Adjustment Expenses

No definition available.

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- Definition

Ceded Future Policy Benefits

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount after valuation allowance recoverable including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6824-158387

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.(a),6)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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- Definition

Amount of valuation allowance for reinsurance recoverables. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

No definition available.

+ Details

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- Definition

Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

No definition available.

+ Details

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- Definition

Amount before valuation allowance of reinsurance recoverables on paid losses.

+ References

No definition available.

+ Details

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