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Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Summary of the disposition of fixed income and equity securities |  |
Fixed income securities, available-for-sale | $ 383,181 | $ 80,245
Fixed income securities, available-for-sale | 343,319 | 242,955
SALES |  |
Summary of the disposition of fixed income and equity securities |  |
Fixed income securities, available-for-sale | 383,956 | 98,696
Gross Realized Gains - Fixed income securities - available-for-sale | 5,076 | 538
Gross Realized Losses - Fixed income securities - available-for-sale | (3,219) | (2,489)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale | 1,857 | (1,951)
Proceeds from Sales - Equity securities | 87,874 | 44,863
Gross Realized Gains - Equity securities | 46,478 | 20,276
Gross Realized Losses - Equity securities | (991) | (340)
Net Realized Gain (Loss) - Equity securities | 45,487 | 19,936
Calls And Maturities Of Marketable Securities |  |
Summary of the disposition of fixed income and equity securities |  |
Fixed income securities, available-for-sale | 344,629 | 240,200
Gross Realized Gains - Fixed income securities - available-for-sale | 271 | 89
Gross Realized Losses - Fixed income securities - available-for-sale | (72) | (1,062)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale | $ 199 | $ (973)

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