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Loans (Tier Risk Rating System) - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
Nonaccrual [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Interest income on nonaccrual loans cash basis | $ 93 | $ 338
Minimum [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Repayment period of loan with a reasonable reduction of principal balance | 2 years |

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