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Fair Value (Assets and liabilities measured at fair value on a recurring basis) (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Fixed maturity securities: |  |
Fixed maturity securities | $ 37,627 | $ 44,380
Equity securities: |  |
Equity securities | 674 | 1,035
Short term and other | 1,679 | 1,872
Total assets | 39,980 | 47,287
Other liabilities | 1 | 12
Total liabilities | 1 | 12
Corporate and other bonds |  |
Fixed maturity securities: |  |
Fixed maturity securities | 22,117 | 24,852
States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Fixed maturity securities | 8,317 | 11,943
Asset-backed |  |
Fixed maturity securities: |  |
Fixed maturity securities | 7,193 | 7,585
Common Stock |  |
Equity securities: |  |
Equity securities | 185 | 233
Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | 489 | 802
Level 1 |  |
Fixed maturity securities: |  |
Fixed maturity securities | 120 | 140
Equity securities: |  |
Equity securities | 204 | 285
Short term and other | 1,608 | 1,798
Total assets | 1,932 | 2,223
Other liabilities | 0 | 0
Total liabilities | 0 | 0
Level 1 | Corporate and other bonds |  |
Fixed maturity securities: |  |
Fixed maturity securities | 120 | 140
Level 1 | States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Fixed maturity securities | 0 | 0
Level 1 | Asset-backed |  |
Fixed maturity securities: |  |
Fixed maturity securities | 0 | 0
Level 1 | Common Stock |  |
Equity securities: |  |
Equity securities | 150 | 220
Level 1 | Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | 54 | 65
Level 2 |  |
Fixed maturity securities: |  |
Fixed maturity securities | 35,866 | 42,691
Equity securities: |  |
Equity securities | 435 | 721
Short term and other | 71 | 74
Total assets | 36,372 | 43,486
Other liabilities | 1 | 12
Total liabilities | 1 | 12
Level 2 | Corporate and other bonds |  |
Fixed maturity securities: |  |
Fixed maturity securities | 21,187 | 23,775
Level 2 | States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Fixed maturity securities | 8,274 | 11,887
Level 2 | Asset-backed |  |
Fixed maturity securities: |  |
Fixed maturity securities | 6,405 | 7,029
Level 2 | Common Stock |  |
Equity securities: |  |
Equity securities | 0 | 0
Level 2 | Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | 435 | 721
Level 3 |  |
Fixed maturity securities: |  |
Fixed maturity securities | 1,641 | 1,549
Equity securities: |  |
Equity securities | 35 | 29
Short term and other | 0 | 0
Total assets | 1,676 | 1,578
Other liabilities | 0 | 0
Total liabilities | 0 | 0
Level 3 | Corporate and other bonds |  |
Fixed maturity securities: |  |
Fixed maturity securities | 810 | 937
Level 3 | States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Fixed maturity securities | 43 | 56
Level 3 | Asset-backed |  |
Fixed maturity securities: |  |
Fixed maturity securities | 788 | 556
Level 3 | Common Stock |  |
Equity securities: |  |
Equity securities | 35 | 13
Level 3 | Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | $ 0 | $ 16

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