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v3.25.1

Investments (Summary of fixed maturity and equity securities) (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024 | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | --- | --- | ---
Fixed maturity securities available-for-sale: |  |  |  |
Cost or Amortized Cost | $ 43,989 | $ 43,481 |  |
Gross Unrealized Gains | 796 | 715 |  |
Gross Unrealized Losses | 2,767 | 3,040 |  |
Allowance for Credit Losses | 47 | 45 | $ 20 | $ 16
Estimated Fair Value | 41,971 | 41,111 |  |
Debt Securities, Trading, Unrealized Gain (Loss) [Abstract] |  |  |  |
Total fixed maturity securities trading | 2 | 0 |  |
Total fixed maturity securities trading | 2 | 0 |  |
Debt securities, amortized cost | 43,991 | 43,481 |  |
Total fixed maturity securities | 41,973 | 41,111 |  |
Corporate and other bonds |  |  |  |
Fixed maturity securities available-for-sale: |  |  |  |
Cost or Amortized Cost | 26,388 | 25,839 |  |
Gross Unrealized Gains | 502 | 423 |  |
Gross Unrealized Losses | 1,149 | 1,305 |  |
Allowance for Credit Losses | 15 | 13 | 3 | 4
Estimated Fair Value | 25,726 | 24,944 |  |
Debt Securities, Trading, Unrealized Gain (Loss) [Abstract] |  |  |  |
Total fixed maturity securities | 26,616 | 25,841 |  |
States, municipalities and political subdivisions |  |  |  |
Fixed maturity securities available-for-sale: |  |  |  |
Cost or Amortized Cost | 7,246 | 7,396 |  |
Gross Unrealized Gains | 227 | 243 |  |
Gross Unrealized Losses | 829 | 835 |  |
Allowance for Credit Losses | 0 | 0 |  |
Estimated Fair Value | 6,644 | 6,804 |  |
Debt Securities, Trading, Unrealized Gain (Loss) [Abstract] |  |  |  |
Total fixed maturity securities | 6,644 | 6,804 |  |
Residential mortgage-backed |  |  |  |
Fixed maturity securities available-for-sale: |  |  |  |
Cost or Amortized Cost | 3,844 | 3,725 |  |
Gross Unrealized Gains | 20 | 7 |  |
Gross Unrealized Losses | 426 | 488 |  |
Allowance for Credit Losses | 0 | 0 |  |
Estimated Fair Value | 3,438 | 3,244 |  |
Commercial mortgage-backed |  |  |  |
Fixed maturity securities available-for-sale: |  |  |  |
Cost or Amortized Cost | 1,788 | 1,830 |  |
Gross Unrealized Gains | 14 | 11 |  |
Gross Unrealized Losses | 119 | 142 |  |
Allowance for Credit Losses | 18 | 18 |  |
Estimated Fair Value | 1,665 | 1,681 |  |
Other asset-backed |  |  |  |
Fixed maturity securities available-for-sale: |  |  |  |
Cost or Amortized Cost | 3,816 | 3,770 |  |
Gross Unrealized Gains | 24 | 24 |  |
Gross Unrealized Losses | 216 | 239 |  |
Allowance for Credit Losses | 14 | 14 |  |
Estimated Fair Value | 3,610 | 3,541 |  |
Asset-backed |  |  |  |
Fixed maturity securities available-for-sale: |  |  |  |
Cost or Amortized Cost | 9,448 | 9,325 |  |
Gross Unrealized Gains | 58 | 42 |  |
Gross Unrealized Losses | 761 | 869 |  |
Allowance for Credit Losses | 32 | 32 | $ 17 | $ 12
Estimated Fair Value | 8,713 | 8,466 |  |
Debt Securities, Trading, Unrealized Gain (Loss) [Abstract] |  |  |  |
Total fixed maturity securities | 8,713 | 8,466 |  |
U.S. Treasury and obligations of government-sponsored enterprises |  |  |  |
Fixed maturity securities available-for-sale: |  |  |  |
Cost or Amortized Cost | 219 | 220 |  |
Gross Unrealized Gains | 1 | 1 |  |
Gross Unrealized Losses | 2 | 1 |  |
Allowance for Credit Losses | 0 | 0 |  |
Estimated Fair Value | 218 | 220 |  |
Foreign government |  |  |  |
Fixed maturity securities available-for-sale: |  |  |  |
Cost or Amortized Cost | 688 | 701 |  |
Gross Unrealized Gains | 8 | 6 |  |
Gross Unrealized Losses | 26 | 30 |  |
Allowance for Credit Losses | 0 | 0 |  |
Estimated Fair Value | $ 670 | $ 677 |  |

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