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Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2025 | Dec. 31, 2024
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Impairment | $ 87 | $ 97
1-4 Family Real Estate Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Impairment | 3 | 2
Agricultural Real Estate Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Impairment | 84 | 95
Collateral Dependent [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Fair Value | 91 | 52
Level 3 [Member] | Collateral Dependent [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Fair Value | $ 3,600 | $ 3,000

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