Investments (Aggregate Fair Value And Gross Unrealized Loss Of Fixed Maturity Securities In An Unrealized Loss Position) (Details) - Fixed Maturity Securities [Member] $ in Millions	Dec. 31, 2022 USD ($) securities	Dec. 31, 2021 USD ($) securities
Investment [Line Items]
Number of Securities, Less than 12 Months \| securities	7,781	3,571
Estimated Fair Value, Less than 12 Months	$ 16,035	$ 8,755
Gross unrealized loss, less than 12 months	$ (1,071)	$ (131)
Number of Securities, 12 Months or Greater \| securities	4,060	686
Estimated Fair Value, 12 Months or Greater	$ 7,537	$ 985
Gross unrealized loss, 12 Months or greater	$ (1,307)	$ (51)
United States Government Securities [Member]
Investment [Line Items]
Number of Securities, Less than 12 Months \| securities	61	51
Estimated Fair Value, Less than 12 Months	$ 701	$ 990
Gross unrealized loss, less than 12 months	$ (40)	$ (11)
Number of Securities, 12 Months or Greater \| securities	38	27
Estimated Fair Value, 12 Months or Greater	$ 442	$ 176
Gross unrealized loss, 12 Months or greater	$ (63)	$ (7)
Government Sponsored Securities [Member]
Investment [Line Items]
Number of Securities, Less than 12 Months \| securities	39	0
Estimated Fair Value, Less than 12 Months	$ 73	$ 0
Gross unrealized loss, less than 12 months	$ (4)	$ 0
Number of Securities, 12 Months or Greater \| securities	6	1
Estimated Fair Value, 12 Months or Greater	$ 5	$ 1
Gross unrealized loss, 12 Months or greater	$ (1)	$ (1)
Foreign Government Securities [Member]
Investment [Line Items]
Number of Securities, Less than 12 Months \| securities	150	188
Estimated Fair Value, Less than 12 Months	$ 100	$ 143
Gross unrealized loss, less than 12 months	$ (10)	$ (8)
Number of Securities, 12 Months or Greater \| securities	198	68
Estimated Fair Value, 12 Months or Greater	$ 142	$ 41
Gross unrealized loss, 12 Months or greater	$ (36)	$ (5)
States, Municipalities And Political Subdivisions, Tax-Exempt [Member]
Investment [Line Items]
Number of Securities, Less than 12 Months \| securities	1,398	281
Estimated Fair Value, Less than 12 Months	$ 2,615	$ 634
Gross unrealized loss, less than 12 months	$ (147)	$ (9)
Number of Securities, 12 Months or Greater \| securities	396	8
Estimated Fair Value, 12 Months or Greater	$ 652	$ 16
Gross unrealized loss, 12 Months or greater	$ (118)	$ (1)
Corporate Securities [Member]
Investment [Line Items]
Number of Securities, Less than 12 Months \| securities	3,551	1,846
Estimated Fair Value, Less than 12 Months	$ 7,826	$ 3,310
Gross unrealized loss, less than 12 months	$ (549)	$ (57)
Number of Securities, 12 Months or Greater \| securities	2,204	403
Estimated Fair Value, 12 Months or Greater	$ 3,521	$ 485
Gross unrealized loss, 12 Months or greater	$ (669)	$ (21)
Residential Mortgage-Backed Securities [Member]
Investment [Line Items]
Number of Securities, Less than 12 Months \| securities	1,341	422
Estimated Fair Value, Less than 12 Months	$ 1,435	$ 1,295
Gross unrealized loss, less than 12 months	$ (121)	$ (19)
Number of Securities, 12 Months or Greater \| securities	496	63
Estimated Fair Value, 12 Months or Greater	$ 982	$ 44
Gross unrealized loss, 12 Months or greater	$ (203)	$ (3)
Commercial Mortgage-Backed Securities [Member]
Investment [Line Items]
Number of Securities, Less than 12 Months \| securities	457	272
Estimated Fair Value, Less than 12 Months	$ 1,082	$ 676
Gross unrealized loss, less than 12 months	$ (76)	$ (8)
Number of Securities, 12 Months or Greater \| securities	324	66
Estimated Fair Value, 12 Months or Greater	$ 719	$ 137
Gross unrealized loss, 12 Months or greater	$ (100)	$ (8)
Other Asset-Backed Securities [Member]
Investment [Line Items]
Number of Securities, Less than 12 Months \| securities	784	511
Estimated Fair Value, Less than 12 Months	$ 2,203	$ 1,707
Gross unrealized loss, less than 12 months	$ (124)	$ (19)
Number of Securities, 12 Months or Greater \| securities	398	50
Estimated Fair Value, 12 Months or Greater	$ 1,074	$ 85
Gross unrealized loss, 12 Months or greater	$ (117)	$ (5)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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