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Investments - Changes in Balance of Level 3 Securities (Details) - Significant Unobservable Inputs (Level 3) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2026 | Mar. 31, 2025
Summary of changes in Level 3 securities |  |
Beginning balance | $ 118,561 | $ 95,125
Included in other comprehensive earnings (loss) | (1,546) | 893
Purchases | 15,296 | 5,070
Sales / Calls / Maturities | (330) | (2,143)
Ending balance | 131,981 | 98,945
Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - OCI | $ (1,550) | $ 893

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