Investments (Analysis Of Cost Or Amortized Cost Gross Unrealized Gains And Losses And Fair Value For Investments) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Schedule of Available-for-sale Securities
Total	$ 14,361	$ 12,979
Fixed maturities, unrealized gains	117	61
Fixed maturities, unrealized losses	687	908
Fair value of fixed maturities	13,791	12,132
Corporate Securities
Schedule of Available-for-sale Securities
Total	7,836	7,412
Fixed maturities, unrealized gains	70	37
Fixed maturities, unrealized losses	454	580
Fair value of fixed maturities	7,452	6,869
States, Municipalities and Political Subdivisions
Schedule of Available-for-sale Securities
Total	4,867	4,901
Fixed maturities, unrealized gains	44	24
Fixed maturities, unrealized losses	208	303
Fair value of fixed maturities	4,703	4,622
Government-Sponsored Enterprises
Schedule of Available-for-sale Securities
Total	1,227	186
Fixed maturities, unrealized gains	3	0
Fixed maturities, unrealized losses	6	3
Fair value of fixed maturities	1,224	183
United States Government
Schedule of Available-for-sale Securities
Total	203	196
Fixed maturities, unrealized gains	0	0
Fixed maturities, unrealized losses	3	5
Fair value of fixed maturities	200	191
Mortgage-backed
Schedule of Available-for-sale Securities
Total	203	250
Fixed maturities, unrealized gains	0	0
Fixed maturities, unrealized losses	16	16
Fair value of fixed maturities	187	234
Foreign Government
Schedule of Available-for-sale Securities
Total	25	34
Fixed maturities, unrealized gains	0	0
Fixed maturities, unrealized losses	0	1
Fair value of fixed maturities	25	33
Fixed Maturities
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	687	908
Fixed Maturities \| Corporate Securities
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	454	580
Fixed Maturities \| States, Municipalities and Political Subdivisions
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	208	303
Fixed Maturities \| Government-Sponsored Enterprises
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	6	3
Fixed Maturities \| United States Government
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	3	5
Fixed Maturities \| Mortgage-backed
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	$ 16	$ 16

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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