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Securities - Schedule of Components of Investment Securities Gains (Losses), Net (Detail) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2026 | Mar. 31, 2025
Available-for-sale debt securities: |  |
Gains realized on sales | $ 403 | $ 390
Equity securities with readily determinable fair values: |  |
Fair value adjustments, net | (287) | 144
Equity securities without readily determinable fair values: |  |
Fair value adjustments, net | 315 | (5,243)
Sales | 2,615 | (73)
Total investment securities gains (losses), net | $ 3,046 | $ (4,782)

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