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Fair Value (Assets and liabilities measured at fair value on a recurring basis) (Details) - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Fixed maturity securities: |  |
Total fixed maturity securities | $ 45,069 | $ 44,631
Equity securities: |  |
Equity securities | 1,045 | 992
Short term and other | 992 | 1,789
Total assets | 47,106 | 47,412
Other liabilities | 12 | 19
Total liabilities | 12 | 19
Corporate and other bonds |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 25,218 | 25,234
States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 11,979 | 11,592
Asset-backed |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 7,872 | 7,805
Common Stock |  |
Equity securities: |  |
Equity securities | 228 | 195
Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | 817 | 797
Level 1 |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 146 | 355
Equity securities: |  |
Equity securities | 276 | 243
Short term and other | 992 | 1,761
Total assets | 1,414 | 2,359
Other liabilities | 0 | 0
Total liabilities | 0 | 0
Level 1 | Corporate and other bonds |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 146 | 355
Level 1 | States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 0 | 0
Level 1 | Asset-backed |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 0 | 0
Level 1 | Common Stock |  |
Equity securities: |  |
Equity securities | 209 | 175
Level 1 | Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | 67 | 68
Level 2 |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 43,511 | 43,152
Equity securities: |  |
Equity securities | 745 | 722
Short term and other | 0 | 28
Total assets | 44,256 | 43,902
Other liabilities | 12 | 19
Total liabilities | 12 | 19
Level 2 | Corporate and other bonds |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 24,195 | 24,109
Level 2 | States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 11,922 | 11,546
Level 2 | Asset-backed |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 7,394 | 7,497
Level 2 | Common Stock |  |
Equity securities: |  |
Equity securities | 0 | 0
Level 2 | Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | 745 | 722
Level 3 |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 1,412 | 1,124
Equity securities: |  |
Equity securities | 24 | 27
Short term and other | 0 | 0
Total assets | 1,436 | 1,151
Other liabilities | 0 | 0
Total liabilities | 0 | 0
Level 3 | Corporate and other bonds |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 877 | 770
Level 3 | States, municipalities and political subdivisions |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 57 | 46
Level 3 | Asset-backed |  |
Fixed maturity securities: |  |
Total fixed maturity securities | 478 | 308
Level 3 | Common Stock |  |
Equity securities: |  |
Equity securities | 19 | 20
Level 3 | Non-redeemable preferred stock |  |
Equity securities: |  |
Equity securities | $ 5 | $ 7

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