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v3.25.3

Fair Value Measurements (Tables) | 9 Months Ended
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Sep. 30, 2025
Fair Value Disclosures [Abstract] |
Assets And Liabilities Measured At Fair value, On A Recurring Basis | The following tables present the assets and liabilities measured at fair value on a recurring basis as of September 30, 2025 and December 31, 2024 by level:
(In thousands) | Total |  | Level 1 |  | Level 2 |  | Level 3
September 30, 2025 |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |
Fixed maturity securities available for sale: |  |  |  |  |  |  |
U.S. government and government agency | $ | 3,478,237 |  |  | $ | — |  |  | $ | 3,478,237 |  |  | $ | — |
State and municipal | 1,974,136 |  |  | — |  |  | 1,974,136 |  |  | — |
Mortgage-backed | 4,969,446 |  |  | — |  |  | 4,969,446 |  |  | — |
Asset-backed | 3,831,174 |  |  | — |  |  | 3,831,174 |  |  | — |
Corporate | 8,740,772 |  |  | — |  |  | 8,720,753 |  |  | 20,019 |
Foreign government | 1,923,864 |  |  | — |  |  | 1,923,864 |  |  | — |
Total fixed maturity securities available for sale | 24,917,629 |  |  | — |  |  | 24,897,610 |  |  | 20,019 |
Equity securities: |  |  |  |  |  |  |
Common stocks | 721,950 |  |  | 718,999 |  |  | 842 |  |  | 2,109 |
Preferred stocks | 660,482 |  |  | — |  |  | 651,808 |  |  | 8,674 |
Total equity securities | 1,382,432 |  |  | 718,999 |  |  | 652,650 |  |  | 10,783 |
Arbitrage trading account | 1,070,304 |  |  | 881,153 |  |  | 189,038 |  |  | 113 |
Total | $ | 27,370,365 |  |  | $ | 1,600,152 |  |  | $ | 25,739,298 |  |  | $ | 30,915 |
Liabilities: |  |  |  |  |  |  |
Trading account securities sold but not yet purchased | $ | 34,509 |  |  | $ | 34,509 |  |  | $ | — |  |  | $ | — |
December 31, 2024 |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |
Fixed maturity securities available for sale: |  |  |  |  |  |  |
U.S. government and government agency | $ | 2,235,341 |  |  | $ | — |  |  | $ | 2,235,341 |  |  | $ | — |
State and municipal | 2,294,644 |  |  | — |  |  | 2,294,644 |  |  | — |
Mortgage-backed | 3,765,490 |  |  | — |  |  | 3,765,490 |  |  | — |
Asset-backed | 3,885,012 |  |  | — |  |  | 3,885,012 |  |  | — |
Corporate | 8,417,641 |  |  | — |  |  | 8,397,974 |  |  | 19,667 |
Foreign government | 1,755,325 |  |  | — |  |  | 1,755,325 |  |  | — |
Total fixed maturity securities available for sale | 22,353,453 |  |  | — |  |  | 22,333,786 |  |  | 19,667 |
Equity securities: |  |  |  |  |  |  |
Common stocks | 760,167 |  |  | 757,115 |  |  | 1,011 |  |  | 2,041 |
Preferred stocks | 443,621 |  |  | — |  |  | 439,947 |  |  | 3,674 |
Total equity securities | 1,203,788 |  |  | 757,115 |  |  | 440,958 |  |  | 5,715 |
Arbitrage trading account | 1,122,599 |  |  | 1,062,459 |  |  | 56,630 |  |  | 3,510 |
Total | $ | 24,679,840 |  |  | $ | 1,819,574 |  |  | $ | 22,831,374 |  |  | $ | 28,892 |
Liabilities: |  |  |  |  |  |  |
Trading account securities sold but not yet purchased | $ | 73,358 |  |  | $ | 73,358 |  |  | $ | — |  |  | $ | — |
Summarize Changes In Level 3 Assets | The following tables summarize changes in Level 3 assets and liabilities for the nine months ended September 30, 2025 and for the year ended December 31, 2024:
Gains (Losses) Included In:
(In thousands) | Beginning Balance |  | (Losses) Earnings |  | Other Comprehensive Income (Losses) |  | Impairments |  | Purchases |  | Sales |  | Paydowns / Maturities |  | Transfers In / (Out) |  | Ending Balance
Nine Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturities securities available for sale: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate | $ | 19,667 |  |  | $ | — |  |  | $ | 352 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 20,019 |
Total | 19,667 |  |  | — |  |  | 352 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 20,019 |
Equity securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stocks | 2,041 |  |  | 194 |  |  | — |  |  | — |  |  | — |  |  | (126) |  |  | — |  |  | — |  |  | 2,109 |
Preferred stocks | 3,674 |  |  | — |  |  | — |  |  | — |  |  | 6,160 |  |  | (1,160) |  |  | — |  |  | — |  |  | 8,674 |
Total | 5,715 |  |  | 194 |  |  | — |  |  | — |  |  | 6,160 |  |  | (1,286) |  |  | — |  |  | — |  |  | 10,783 |
Arbitrage trading account | 3,510 |  |  | (3,398) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 1 |  |  | 113 |
Total | $ | 28,892 |  |  | $ | (3,204) |  |  | $ | 352 |  |  | $ | — |  |  | $ | 6,160 |  |  | $ | (1,286) |  |  | $ | — |  |  | $ | 1 |  |  | $ | 30,915 |
Year Ended December 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturities securities available for sale: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate | $ | — |  |  | $ | — |  |  | $ | (333) |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 20,000 |  |  | $ | 19,667 |
Total | — |  |  | — |  |  | (333) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 20,000 |  |  | 19,667 |
Equity securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stocks | 1,558 |  |  | 611 |  |  | — |  |  | — |  |  | — |  |  | (128) |  |  | — |  |  | — |  |  | 2,041 |
Preferred stocks | 3,695 |  |  | 36 |  |  | — |  |  | — |  |  | — |  |  | (57) |  |  | — |  |  | — |  |  | 3,674 |
Total | 5,253 |  |  | 647 |  |  | — |  |  | — |  |  | — |  |  | (185) |  |  | — |  |  | — |  |  | 5,715 |
Arbitrage trading account | 3,772 |  |  | (261) |  |  | — |  |  | — |  |  | — |  |  | (38) |  |  | — |  |  | 37 |  |  | 3,510 |
Total | $ | 9,025 |  |  | $ | 386 |  |  | $ | (333) |  |  | $ | — |  |  | $ | — |  |  | $ | (223) |  |  | $ | — |  |  | $ | 20,037 |  |  | $ | 28,892 |

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