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Investments - Changes in Balance of Level 3 Securities (Details) - Significant Unobservable Inputs (Level 3) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Summary of changes in Level 3 securities |  |  |  |
Beginning balance | $ 101,534 | $ 72,680 | $ 95,125 | $ 62,096
Included in other comprehensive earnings (loss) | 1,130 | 3,104 | 2,922 | 2,789
Purchases | 6,995 | 16,069 | 15,093 | 28,379
Sales / Calls / Maturities | (8,149) | (326) | (11,630) | (1,737)
Ending balance | 101,510 | 91,527 | 101,510 | 91,527
Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - OCI | $ 1,244 | $ 3,104 | $ 2,899 | $ 2,789

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