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Fair Values of Assets and Liabilities - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Random sample percentage of securities for each quarter | 100.00% |
Corporate securities transferred from Level 3 to Level 2 |  | $ 0
Impaired loans considered to be credit risk of non-collection | $ 250,000 |
Updated appraisal requirement floor | 250,000 |
Other real estate owned | 895,000 | 422,000
Financial instrument of credit risk | 300,000 | 100,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings On Assets Held At Year End | 0 | $ 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Between Levels 1 And 2 | $ 0 |

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