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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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Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

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Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment	$ 1,300		$ 883
Transferred of assets in or out of level 3	0		0
1-4 Family Real Estate Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment	5	$ 3	5
Agricultural Real Estate Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment	1,300	$ 84
Collateral Dependent [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	211		145
Level 3 [Member] \| Collateral Dependent [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	$ 4,000		$ 860