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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

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