Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
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	61	51
Reserves for structured settlements	$ 5,273	$ 5,085
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	835	861
Reserves for structured settlements	$ 161	$ 170

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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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
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Amount of accrued obligation to policyholders that relates to insured events under individual and group annuities and supplementary insurance contracts.

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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

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