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Securities - Unrealized Gains (Losses) of Debt Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Gross Unrealized Gains |  |
Total unrealized gains (losses) on available-for-sale debt securities | $ 623 | $ 1,746
Income tax (expense) benefit | (134) | (372)
Net Unrealized Gains (Losses), Net of Tax Included in Accumulated Other Comprehensive Income (Loss) | 489 | 1,374
Gross Unrealized Losses |  |
Total unrealized gains (losses) on available-for-sale debt securities | (88,411) | (83,751)
Income tax (expense) benefit | 19,041 | 17,824
Net Unrealized Gains (Losses), Net of Tax Included in Accumulated Other Comprehensive Income (Loss) | (69,370) | (65,927)
Net Unrealized Losses |  |
Total unrealized gains (losses) on available-for-sale debt securities | (87,788) | (82,005)
Income tax (expense) benefit | 18,907 | 17,452
Net Unrealized Gains (Losses), Net of Tax Included in Accumulated Other Comprehensive Income (Loss) | $ (68,881) | $ (64,553)

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