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Investments - (Narrative) (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 USD ($) security | Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($) security
Investments [Abstract] |  |  |
Equity Securities at Fair Value | $ 11,118 |  | $ 11,185
Fair value of largest single common stock holding | $ 786 |  | $ 891
Largest equity holdings to total equity portfolio | 7.30% |  | 8.20%
Largest equity holdings to total investment portfolio | 2.80% |  | 3.20%
Allowance for credit loss on fixed-maturity | $ 35 |  | $ 33
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Securities Sold | $ 0 | $ 0 |
Number of fixed-maturity securities in a total unrealized loss position | security | 3,679 |  | 3,723
Fixed-maturity securities, total unrealized loss | $ 582 |  | $ 631
Number of fixed-maturity securities in continuous unrealized loss position and below 70 percent of amortized cost | 34 |  | 19
Fixed maturity investments, Percentage of amortized costs | 70.00% |  |

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