Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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