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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, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] |  |  |
Unrealized gain (loss) on available-for-sale securities, Pre-Tax Amount | $ 7,850 | $ (31,602) | $ (6,695)
Reclassification adjustment for gains (losses) realized in net income, Pre-Tax Amount | 547 | (3,037) | (2,776)
Net unrealized gain loss, Pre-Tax Amount | 8,397 | (34,639) | (9,471)
Other comprehensive income (loss), Pre-Tax Amount | 8,397 | (34,639) | (9,471)
Unrealized gain loss on available-for-sale securities, Tax Expense (Benefit) | 1,648 | (6,636) | (1,406)
Reclassification adjustment for gains (losses) realized in net income, Tax Expense (Benefit) | 115 | (638) | (583)
Net unrealized gain loss, Tax Expense (Benefit) | 1,763 | (7,274) | (1,989)
Other comprehensive income (loss), Tax Expense (Benefit) | 1,763 | (7,274) | (1,989)
Unrealized gain (loss) on available-for-sale securities, Net-of-Tax Amount | 6,202 | (24,966) | (5,289)
Reclassification adjustment for gains (losses) realized in net income, Net-of-Tax Amount | 432 | (2,399) | (2,193)
Net unrealized gain loss, Net-of-Tax Amount | 6,634 | (27,365) | (7,482)
Other comprehensive income (loss), Net-of-Tax Amount | $ 6,634 | $ (27,365) | $ (7,482)

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