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Fair Value (Assets and liabilities measured at fair value on a recurring basis) (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Fixed maturity securities: |  |
Fixed maturity securities | $ 44,380 | $ 44,631
Equity securities: |  |
Equity securities | 1,035 | 992
Short term and other | 1,872 | 1,789
Total assets | 47,287 | 47,412
Other liabilities | 12 | 19
Total liabilities | 12 | 19
Corporate and other bonds |  |
Fixed maturity securities: |  |
Fixed maturity securities | 24,852 | 25,234
States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Fixed maturity securities | 11,943 | 11,592
Asset-backed |  |
Fixed maturity securities: |  |
Fixed maturity securities | 7,585 | 7,805
Common Stock |  |
Equity securities: |  |
Equity securities | 233 | 195
Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | 802 | 797
Level 1 |  |
Fixed maturity securities: |  |
Fixed maturity securities | 140 | 355
Equity securities: |  |
Equity securities | 285 | 243
Short term and other | 1,798 | 1,761
Total assets | 2,223 | 2,359
Other liabilities | 0 | 0
Total liabilities | 0 | 0
Level 1 | Corporate and other bonds |  |
Fixed maturity securities: |  |
Fixed maturity securities | 140 | 355
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 | 220 | 175
Level 1 | Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | 65 | 68
Level 2 |  |
Fixed maturity securities: |  |
Fixed maturity securities | 42,691 | 43,152
Equity securities: |  |
Equity securities | 721 | 722
Short term and other | 74 | 28
Total assets | 43,486 | 43,902
Other liabilities | 12 | 19
Total liabilities | 12 | 19
Level 2 | Corporate and other bonds |  |
Fixed maturity securities: |  |
Fixed maturity securities | 23,775 | 24,109
Level 2 | States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Fixed maturity securities | 11,887 | 11,546
Level 2 | Asset-backed |  |
Fixed maturity securities: |  |
Fixed maturity securities | 7,029 | 7,497
Level 2 | Common Stock |  |
Equity securities: |  |
Equity securities | 0 | 0
Level 2 | Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | 721 | 722
Level 3 |  |
Fixed maturity securities: |  |
Fixed maturity securities | 1,549 | 1,124
Equity securities: |  |
Equity securities | 29 | 27
Short term and other | 0 | 0
Total assets | 1,578 | 1,151
Other liabilities | 0 | 0
Total liabilities | 0 | 0
Level 3 | Corporate and other bonds |  |
Fixed maturity securities: |  |
Fixed maturity securities | 937 | 770
Level 3 | States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Fixed maturity securities | 56 | 46
Level 3 | Asset-backed |  |
Fixed maturity securities: |  |
Fixed maturity securities | 556 | 308
Level 3 | Common Stock |  |
Equity securities: |  |
Equity securities | 13 | 20
Level 3 | Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | $ 16 | $ 7

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