Fair Value - Summary of Assets Measured at Fair Value on Non-recurring Basis (Detail) - Assets Measured at Fair Value on a Non-recurring Basis [Member] - Level 3 [Member] - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Loans Individually Evaluated for Credit Losses [Member] \| Commercial Real Estate [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on non-recurring basis	$ 9,580	$ 5,119
Loans Individually Evaluated for Credit Losses [Member] \| Commercial and Industrial [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on non-recurring basis	18,616	18,517
Loans Individually Evaluated for Credit Losses [Member] \| Residential Real Estate [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on non-recurring basis	2,635	2,829
Loans Individually Evaluated for Credit Losses [Member] \| Agricultural Real Estate [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on non-recurring basis	1,274	905
Loans Individually Evaluated for Credit Losses [Member] \| Other [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on non-recurring basis	763	1,257
Other Real Estate Owned [Member] \| Commercial Real Estate [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on non-recurring basis	2,173	2,173
Other Real Estate Owned [Member] \| Residential Real Estate [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on non-recurring basis	$ 33	$ 25