Allowance for Credit Losses - Changes in the Allowance for Credit Losses (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	$ 42,020	$ 39,669	$ 39,669
Charge-offs	(806)	(976)
Recoveries	90	343
Provision	(768)	1,248
Ending Balance	40,536	40,284	42,020
Commercial and Agriculture [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	5,153	6,586	6,586
Charge-offs	(96)	(72)
Recoveries	62	291
Provision	(123)	(611)
Ending Balance	4,996	6,194	5,153
Commercial Real Estate Owner Occupied [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	4,420	4,327	4,327
Recoveries	2
Provision	(142)	139
Ending Balance	4,280	4,466	4,420
Commercial Real Estate Non Owner Occupied [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	12,118	11,404	11,404
Charge-offs	(484)	(800)
Recoveries	1
Provision	154	808
Ending Balance	11,789	11,412	12,118
Residential Real Estate [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	14,718	11,866	11,866
Charge-offs	(3)
Recoveries	13	19
Provision	(242)	570
Ending Balance	14,486	12,455	14,718
Real Estate Construction [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	3,842	3,708	3,708
Provision	(340)	309
Ending Balance	3,502	4,017	3,842
Farm Real Estate [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	279	226	226
Provision	(54)	38
Ending Balance	225	264	279
Lease Financing Receivable [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	1,169	1,361	1,361
Charge-offs	(210)	(90)
Recoveries	4	25
Provision	45	(19)
Ending Balance	1,008	1,277	1,169
Consumer and Other [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	321	191	191
Charge-offs	(13)	(14)
Recoveries	8	8
Provision	(66)	14
Ending Balance	$ 250	$ 199	$ 321

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 allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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