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Securities - Unrealized Gains (Losses) of Debt Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
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Gross Unrealized Gains |  |
Total unrealized gains (losses) on available-for-sale debt securities | $ 1,746 | $ 261
Income tax (expense) benefit | (372) | (56)
Net Unrealized Gains (Losses), Net of Tax Included in Accumulated Other Comprehensive Income (Loss) | 1,374 | 205
Gross Unrealized Losses |  |
Total unrealized gains (losses) on available-for-sale debt securities | (83,751) | (102,582)
Income tax (expense) benefit | 17,824 | 21,915
Net Unrealized Gains (Losses), Net of Tax Included in Accumulated Other Comprehensive Income (Loss) | (65,927) | (80,667)
Net Unrealized Losses |  |
Total unrealized gains (losses) on available-for-sale debt securities | (82,005) | (102,321)
Income tax (expense) benefit | 17,452 | 21,859
Net Unrealized Gains (Losses), Net of Tax Included in Accumulated Other Comprehensive Income (Loss) | $ (64,553) | $ (80,462)

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