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Securities - Schedule of Components of Investment Securities (Losses) Gains, Net (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Available-for-sale debt securities: |  |  |  |
Gains realized on sales | $ 91 |  | $ 514 | $ 139
Equity securities with readily determinable fair values: |  |  |  |
Fair value adjustments, net | (7,103) | $ 340 | 22,513 | 291
Equity securities without readily determinable fair values: |  |  |  |
Fair value adjustments, net | 2,919 | 738 | (2,384) | (2,277)
Sales |  | 1,545 | 8,167 | 11,974
Total investment securities (losses) gains, net | $ (4,093) | $ 2,623 | $ 28,810 | $ 10,127

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- Definition Amount of unrealized and realized gain (loss) on investment in debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 + Details
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