Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Principal amount of debt	$ 793	$ 793
Recorded outstanding principal and interest for these life policy loans	62	75
Reserves for structured settlements	$ 4,718	$ 4,485
Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Percentage of Level 3 assets measured at fair value	1.00%	1.00%
Life Policy Loans
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Recorded outstanding principal and interest for these life policy loans	$ 31	$ 31
Deferred Annuities and Structured Settlements
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Recorded reserves for the deferred annuities	860	863
Reserves for structured settlements	$ 174	$ 182

Percentage of Level 3 Assets to Total Financial Instruments Measured At Fair Value

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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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.

+ References

No definition available.

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- Definition

The amount needed to reflect the estimated ultimate cost of settling claims relating to casualty insurance insured events that have occurred on or before a particular date (ordinarily, the balance sheet date) and the amount needed to provide for the estimated ultimate cost required to investigate and settle claims relating to insured events that have occurred on or before a particular date (ordinarily, the balance sheet date), whether or not reported to the insurer at that date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a),(b),(c)
-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 18
-Article 12

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- Definition

Amount of accrued obligation to policyholders that relates to insured events under individual and group annuities and supplementary insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 40
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-URI http://asc.fasb.org/extlink&oid=28366191&loc=d3e13145-158430

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-Name Accounting Standards Codification
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 13
-Subparagraph a
-Article 7

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
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