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Fair Value Disclosures - Summary of Loans Held-for-Sale at Fair Value (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024 | Sep. 30, 2024
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Fair Value Measurements Loans Held For Sale [Abstract] |  |  |
Unpaid principal balance on loans held-for-sale | $ 24,453 | $ 7,636 | $ 16,086
Net unrealized gains on loans held-for-sale | 727 | 157 | 427
Loans held-for-sale at fair value | $ 25,180 | $ 7,793 | $ 16,513

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