Investments (Analysis Of Cost Or Amortized Cost Gross Unrealized Gains And Losses And Fair Value For Investments) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities
Total	$ 12,979	$ 12,230
Fixed maturities, unrealized gains	61	808
Fixed maturities, unrealized losses	908	16
Fair value of fixed maturities	12,132	13,022
Corporate Securities
Schedule of Available-for-sale Securities
Total	7,412	7,043
Fixed maturities, unrealized gains	37	467
Fixed maturities, unrealized losses	580	13
Fair value of fixed maturities	6,869	7,497
States, Municipalities and Political Subdivisions
Schedule of Available-for-sale Securities
Total	4,901	4,768
Fixed maturities, unrealized gains	24	330
Fixed maturities, unrealized losses	303	3
Fair value of fixed maturities	4,622	5,095
Commercial Mortgage Backed Securities
Schedule of Available-for-sale Securities
Total	250	264
Fixed maturities, unrealized gains	0	9
Fixed maturities, unrealized losses	16	0
Fair value of fixed maturities	234	273
United States Government
Schedule of Available-for-sale Securities
Total	196	121
Fixed maturities, unrealized gains	0	2
Fixed maturities, unrealized losses	5	0
Fair value of fixed maturities	191	123
Government-Sponsored Enterprises
Schedule of Available-for-sale Securities
Total	186	8
Fixed maturities, unrealized gains	0	0
Fixed maturities, unrealized losses	3	0
Fair value of fixed maturities	183	8
Foreign Government
Schedule of Available-for-sale Securities
Total	34	26
Fixed maturities, unrealized gains	0	0
Fixed maturities, unrealized losses	1	0
Fair value of fixed maturities	33	26
Fixed Maturities
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	908	16
Fixed Maturities \| Corporate Securities
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	580	13
Fixed Maturities \| States, Municipalities and Political Subdivisions
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	303	3
Fixed Maturities \| Commercial Mortgage Backed Securities
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	16	0
Fixed Maturities \| United States Government
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	5	0
Fixed Maturities \| Government-Sponsored Enterprises
Schedule of Available-for-sale Securities
Fixed maturities, unrealized losses	$ 3	$ 0

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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Amount, before tax, of unrealized loss 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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Amortized cost of 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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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