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Derivative Financial Instruments - Summary of Outstanding Notional Balances and Fair Values of Outstanding Derivative Positions (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024 | Sep. 30, 2024
--- | --- | --- | ---
IRLCs [Member] |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |
Outstanding Notional Balance | $ 65,636 | $ 28,584 | $ 50,053
Asset Derivative Fair Value | 726 | 238 | 499
Liability Derivative Fair Value | 0 | 0 | 0
Forward Mortgage-Backed Securities Trades [Member] |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |
Outstanding Notional Balance | 100,000 | 38,500 | 63,000
Asset Derivative Fair Value | 0 | 84 | 0
Liability Derivative Fair Value | $ 214 | $ 0 | $ 98

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