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Summary of Significant Accounting Policies - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
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Unrealized gain (loss) on available-for-sale securities | $ (69,641) | $ (89,041)
Unrealized gain (loss) on held to maturity securities | (2,720) | (3,053)
Unrealized gain (loss) on derivative instruments | 7,072 | 1,212
Tax effect | 13,711 | 19,085
Accumulated other comprehensive income (loss) | $ (51,578) | $ (71,797)

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