Fair Value Measurements (Fair Value Of Deferred Annuities, Structured Settlements And Other Items) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	$ 927	$ 1,044
Deferred Annuities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	742	834
Structured Settlements
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	185	210
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	185	210
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	185	210
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	742	834
Level 3 | Deferred Annuities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis
Fair value of deferred annuities and structured settlements	742	834
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