Investments (Analysis Of Cost Or Amortized Cost Gross Unrealized Gains And Losses And Fair Value For Investments) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities
Total	$ 12,230	$ 11,312
Fair value of fixed maturities	13,022	12,338
Fixed Maturities
Schedule of Available-for-sale Securities
Total	12,230	11,312
Fixed maturities, unrealized gains	808	1,036
Fixed maturities, unrealized losses	16	10
Fair value of fixed maturities	13,022	12,338
Fixed Maturities \| Corporate Securities
Schedule of Available-for-sale Securities
Total	7,043	6,281
Fixed maturities, unrealized gains	467	621
Fixed maturities, unrealized losses	13	7
Fair value of fixed maturities	7,497	6,895
Fixed Maturities \| States, Municipalities and Political Subdivisions
Schedule of Available-for-sale Securities
Total	4,768	4,604
Fixed maturities, unrealized gains	330	395
Fixed maturities, unrealized losses	3	2
Fair value of fixed maturities	5,095	4,997
Fixed Maturities \| Commercial Mortgage Backed Securities
Schedule of Available-for-sale Securities
Total	264	271
Fixed maturities, unrealized gains	9	15
Fixed maturities, unrealized losses	0	1
Fair value of fixed maturities	273	285
Fixed Maturities \| United States Government
Schedule of Available-for-sale Securities
Total	121	115
Fixed maturities, unrealized gains	2	5
Fixed maturities, unrealized losses	0	0
Fair value of fixed maturities	123	120
Fixed Maturities \| Foreign Government
Schedule of Available-for-sale Securities
Total	26	29
Fixed maturities, unrealized gains	0	0
Fixed maturities, unrealized losses	0	0
Fair value of fixed maturities	26	29
Fixed Maturities \| Government-Sponsored Enterprises
Schedule of Available-for-sale Securities
Total	8	12
Fixed maturities, unrealized gains	0	0
Fixed maturities, unrealized losses	0	0
Fair value of fixed maturities	$ 8	$ 12

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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