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Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Loss Contingencies [Line Items] |  |
Commitments to extend credit to commercial customers | $ 12,600,000 | $ 12,700,000
Maximum credit risk for recourse associated with loans sold under Federal National Mortgage Association Delegated Underwriting and Servicing program | 4,300,000 | 4,200,000
Loss contingency accrual | 133,000 | $ 157,000
Minimum |  |
Loss Contingencies [Line Items] |  |
Range of reasonably possible losses | 0 |
Maximum |  |
Loss Contingencies [Line Items] |  |
Range of reasonably possible losses | $ 25,000 |

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