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Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Transferred of assets in or out of level 3 | $ 0 |
Transferred of liabilities in or out of level 3 | 0 |
Impairment | 97 | $ 7
Collateral Dependent [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Specific allocation for collateral dependent impaired loans | 52 | 386
Level 3 [Member] | Collateral Dependent [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Collateral dependent loans categorized as Level 3 | 3,000 | 22,700
1-4 Family Real Estate Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Impairment | 2 | 2
Agricultural Real Estate Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Impairment | $ 95 | $ 5

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