Fair Value Measurements (Fair Value Of Deferred Annuities, Structured Settlements And Other Items) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	$ 1,045	$ 1,094
Deferred Annuities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	839	886
Structured Settlements
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	206	208
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	0	0
Level 1 | Deferred Annuities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	0	0
Level 1 | Structured Settlements
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	0	0
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	206	208
Level 2 | Deferred Annuities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	0	0
Level 2 | Structured Settlements
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	206	208
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	839	886
Level 3 | Deferred Annuities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	839	886
Level 3 | Structured Settlements
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	$ 0	$ 0