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Comprehensive Income and Accumulated Other Comprehensive Income (Loss) - Other Comprehensive Income (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] |  |  |
Unrealized gain (loss) on available-for-sale securities, Pre-Tax Amount | $ (2,429) | $ 7,850 | $ (31,602)
Reclassification adjustment for gains (losses) realized in net income, Pre-Tax Amount | 302 | 547 | (3,037)
Net unrealized gain loss, Pre-Tax Amount | (2,127) | 8,397 | (34,639)
Other comprehensive income (loss), Pre-Tax Amount | (2,127) | 8,397 | (34,639)
Unrealized gain loss on available-for-sale securities, Tax Expense (Benefit) | (510) | 1,648 | (6,636)
Reclassification adjustment for gains (losses) realized in net income, Tax Expense (Benefit) | 64 | 115 | (638)
Net unrealized gain loss, Tax Expense (Benefit) | (446) | 1,763 | (7,274)
Other comprehensive income (loss), Tax Expense (Benefit) | (446) | 1,763 | (7,274)
Unrealized gain (loss) on available-for-sale securities, Net-of-Tax Amount | (1,919) | 6,202 | (24,966)
Reclassification adjustment for gains (losses) realized in net income, Net-of-Tax Amount | 238 | 432 | (2,399)
Net unrealized gain loss, Net-of-Tax Amount | (1,681) | 6,634 | (27,365)
Other comprehensive income (loss), Net-of-Tax Amount | $ (1,681) | $ 6,634 | $ (27,365)

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