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Investments (Fair Values And Unrealized Losses By Investment Category And By The Duration Of The Securities' Continuous Unrealized Loss Position) (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Investments, Unrealized Loss Position |  |
Total Unrealized Losses | $ 687 | $ 908
Corporate Securities |  |
Investments, Unrealized Loss Position |  |
Total Unrealized Losses | 454 | 580
States, Municipalities and Political Subdivisions |  |
Investments, Unrealized Loss Position |  |
Total Unrealized Losses | 208 | 303
Government-Sponsored Enterprises |  |
Investments, Unrealized Loss Position |  |
Total Unrealized Losses | 6 | 3
United States Government |  |
Investments, Unrealized Loss Position |  |
Total Unrealized Losses | 3 | 5
Mortgage-backed |  |
Investments, Unrealized Loss Position |  |
Total Unrealized Losses | 16 | 16
Fixed Maturities |  |
Investments, Unrealized Loss Position |  |
Less than 12 months fair value | 1,384 | 8,760
Less than 12 Months, Unrealized losses | 18 | 706
12 months or more fair value | 7,912 | 800
12 Months or more, unrealized losses | 669 | 202
Total fair value | 9,296 | 9,560
Total Unrealized Losses | 687 | 908
Fixed Maturities | Corporate Securities |  |
Investments, Unrealized Loss Position |  |
Less than 12 months fair value | 379 | 5,651
Less than 12 Months, Unrealized losses | 13 | 412
12 months or more fair value | 5,560 | 661
12 Months or more, unrealized losses | 441 | 168
Total fair value | 5,939 | 6,312
Total Unrealized Losses | 454 | 580
Fixed Maturities | States, Municipalities and Political Subdivisions |  |
Investments, Unrealized Loss Position |  |
Less than 12 months fair value | 313 | 2,600
Less than 12 Months, Unrealized losses | 2 | 274
12 months or more fair value | 1,932 | 77
12 Months or more, unrealized losses | 206 | 29
Total fair value | 2,245 | 2,677
Total Unrealized Losses | 208 | 303
Fixed Maturities | Government-Sponsored Enterprises |  |
Investments, Unrealized Loss Position |  |
Less than 12 months fair value | 652 | 123
Less than 12 Months, Unrealized losses | 3 | 3
12 months or more fair value | 113 | 3
12 Months or more, unrealized losses | 3 | 0
Total fair value | 765 | 126
Total Unrealized Losses | 6 | 3
Fixed Maturities | United States Government |  |
Investments, Unrealized Loss Position |  |
Less than 12 months fair value | 32 | 146
Less than 12 Months, Unrealized losses | 0 | 3
12 months or more fair value | 129 | 41
12 Months or more, unrealized losses | 3 | 2
Total fair value | 161 | 187
Total Unrealized Losses | 3 | 5
Fixed Maturities | Mortgage-backed |  |
Investments, Unrealized Loss Position |  |
Less than 12 months fair value | 5 | 215
Less than 12 Months, Unrealized losses | 0 | 13
12 months or more fair value | 172 | 14
12 Months or more, unrealized losses | 16 | 3
Total fair value | 177 | 229
Total Unrealized Losses | 16 | 16
Fixed Maturities | Foreign government |  |
Investments, Unrealized Loss Position |  |
Less than 12 months fair value | 3 | 25
Less than 12 Months, Unrealized losses | 0 | 1
12 months or more fair value | 6 | 4
12 Months or more, unrealized losses | 0 | 0
Total fair value | 9 | 29
Total Unrealized Losses | $ 0 | $ 1

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