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Fair Value - Fair Value Measurements on a Recurring Basis by Asset Class and Level of Input (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
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Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | $ 1,126,148 |
Fair value of securities lent | 35,500 |
Total available-for-sale securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 1,126,148 | $ 1,043,615
Fair value of securities lent | 18,400 |
Corporate debt securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 705,219 | 643,943
Fair value of securities lent |  | 7,300
Collateralized debt obligations |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 108,911 | 114,127
Commercial mortgage-backed securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 124,192 | 124,982
Residential mortgage-backed securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 144,621 | 133,812
Other debt securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 35,927 | 26,751
U.S. Treasury |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 7,278 |
Equity securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Fair value of securities lent | 17,100 |
Fair Value, Measurements, Recurring Basis |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total | 1,211,376 | 1,129,506
Fair Value, Measurements, Recurring Basis | Total available-for-sale securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 1,126,148 | 1,043,615
Fair Value, Measurements, Recurring Basis | Corporate debt securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 705,219 | 643,943
Fair Value, Measurements, Recurring Basis | Collateralized debt obligations |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 108,911 | 114,127
Fair Value, Measurements, Recurring Basis | Commercial mortgage-backed securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 124,192 | 124,982
Fair Value, Measurements, Recurring Basis | Residential mortgage-backed securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 144,621 | 133,812
Fair Value, Measurements, Recurring Basis | Other debt securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 35,927 | 26,751
Fair Value, Measurements, Recurring Basis | U.S. Treasury |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 7,278 |
Fair Value, Measurements, Recurring Basis | Equity securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 85,228 | 85,891
Fair Value, Measurements, Recurring Basis | Equity securities | Financial services sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 71,184 | 69,930
Fair Value, Measurements, Recurring Basis | Equity securities | Utilities sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 4,593 | 5,629
Fair Value, Measurements, Recurring Basis | Equity securities | Energy sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 2,039 | 4,117
Fair Value, Measurements, Recurring Basis | Equity securities | Consumer sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 4,513 | 3,341
Fair Value, Measurements, Recurring Basis | Equity securities | Technology sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 1,974 | 1,974
Fair Value, Measurements, Recurring Basis | Equity securities | Communications sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 925 | 900
Fair Value, Measurements, Recurring Basis | Level 1 |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total | 2,018 | 1,106
Fair Value, Measurements, Recurring Basis | Level 1 | Total available-for-sale securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Corporate debt securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Collateralized debt obligations |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Commercial mortgage-backed securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Residential mortgage-backed securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Other debt securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | U.S. Treasury |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 |
Fair Value, Measurements, Recurring Basis | Level 1 | Equity securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 2,018 | 1,106
Fair Value, Measurements, Recurring Basis | Level 1 | Equity securities | Financial services sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 2,018 | 1,052
Fair Value, Measurements, Recurring Basis | Level 1 | Equity securities | Utilities sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Equity securities | Energy sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Equity securities | Consumer sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 0 | 54
Fair Value, Measurements, Recurring Basis | Level 1 | Equity securities | Technology sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Equity securities | Communications sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 2 |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total | 1,176,108 | 1,091,069
Fair Value, Measurements, Recurring Basis | Level 2 | Total available-for-sale securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 1,103,538 | 1,013,258
Fair Value, Measurements, Recurring Basis | Level 2 | Corporate debt securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 699,043 | 637,675
Fair Value, Measurements, Recurring Basis | Level 2 | Collateralized debt obligations |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 108,911 | 114,127
Fair Value, Measurements, Recurring Basis | Level 2 | Commercial mortgage-backed securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 107,758 | 100,893
Fair Value, Measurements, Recurring Basis | Level 2 | Residential mortgage-backed securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 144,621 | 133,812
Fair Value, Measurements, Recurring Basis | Level 2 | Other debt securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 35,927 | 26,751
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Treasury |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 7,278 |
Fair Value, Measurements, Recurring Basis | Level 2 | Equity securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 72,570 | 77,811
Fair Value, Measurements, Recurring Basis | Level 2 | Equity securities | Financial services sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 63,661 | 65,378
Fair Value, Measurements, Recurring Basis | Level 2 | Equity securities | Utilities sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 4,593 | 5,629
Fair Value, Measurements, Recurring Basis | Level 2 | Equity securities | Energy sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 2,039 | 4,117
Fair Value, Measurements, Recurring Basis | Level 2 | Equity securities | Consumer sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 1,352 | 1,787
Fair Value, Measurements, Recurring Basis | Level 2 | Equity securities | Technology sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 2 | Equity securities | Communications sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 925 | 900
Fair Value, Measurements, Recurring Basis | Level 3 |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total | 33,250 | 37,331
Fair Value, Measurements, Recurring Basis | Level 3 | Total available-for-sale securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 22,610 | 30,357
Fair Value, Measurements, Recurring Basis | Level 3 | Corporate debt securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 6,176 | 6,268
Fair Value, Measurements, Recurring Basis | Level 3 | Collateralized debt obligations |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Commercial mortgage-backed securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 16,434 | 24,089
Fair Value, Measurements, Recurring Basis | Level 3 | Residential mortgage-backed securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Other debt securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | U.S. Treasury |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total available-for-sale securities | 0 |
Fair Value, Measurements, Recurring Basis | Level 3 | Equity securities |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 10,640 | 6,974
Fair Value, Measurements, Recurring Basis | Level 3 | Equity securities | Financial services sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 5,505 | 3,500
Fair Value, Measurements, Recurring Basis | Level 3 | Equity securities | Utilities sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Equity securities | Energy sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Equity securities | Consumer sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 3,161 | 1,500
Fair Value, Measurements, Recurring Basis | Level 3 | Equity securities | Technology sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | 1,974 | 1,974
Fair Value, Measurements, Recurring Basis | Level 3 | Equity securities | Communications sector |  |
Fair value measurements on a recurring basis by asset class and level of input |  |
Total equity securities | $ 0 | $ 0

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