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Loans - Schedule of Collateral-dependent Loans (Detail) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Collateral dependent loans | $ 4,113 | $ 2,988
Consumer Real Estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Collateral dependent loans | 3,123 | 2,384
Agricultural Real Estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Collateral dependent loans | 371 | 125
Agricultural Loan [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Collateral dependent loans | 50 | 50
Commercial Real Estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Collateral dependent loans | 500 | 360
Commercial and Industrial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Collateral dependent loans | 28 | 28
Consumer [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Collateral dependent loans | $ 41 | $ 41

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