Allowance for Credit Losses - Changes in the Allowance for Credit Losses (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	$ 40,455	$ 39,919	$ 39,669	$ 37,160	$ 37,160
Charge-offs	(662)	(42)	(2,730)	(1,580)
Recoveries	83	45	518	500
Provision	378	1,346	2,797	5,188
Ending Balance	40,254	41,268	40,254	41,268	39,669
Commercial and Agriculture [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	6,057	5,348	6,586	7,587	7,587
Charge-offs	(249)	0	(684)	(1,079)
Recoveries	39	15	375	263
Provision	531	(284)	101	(1,692)
Ending Balance	6,378	5,079	6,378	5,079	6,586
Commercial Real Estate Owner Occupied [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	4,612	4,328	4,327	4,723	4,723
Recoveries		0		0
Provision	74	37	359	(358)
Ending Balance	4,686	4,365	4,686	4,365	4,327
Commercial Real Estate Non Owner Occupied [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	11,321	14,421	11,404	12,056	12,056
Charge-offs			(1,350)	(174)
Recoveries		0	3	12
Provision	(1,189)	126	75	2,653
Ending Balance	10,132	14,547	10,132	14,547	11,404
Residential Real Estate [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	13,075	9,416	11,866	8,489	8,489
Charge-offs	(14)	(1)	(130)	(67)
Recoveries	35	19	76	178
Provision	890	1,288	2,174	2,122
Ending Balance	13,986	10,722	13,986	10,722	11,866
Real Estate Construction [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	3,695	3,647	3,708	3,388	3,388
Recoveries		0		12
Provision	(141)	69	(154)	316
Ending Balance	3,554	3,716	3,554	3,716	3,708
Farm Real Estate [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	305	261	226	260	260
Provision	(4)	(40)	75	(39)
Ending Balance	301	221	301	221	226
Lease Financing Receivable [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	1,214	2,210	1,361	297	297
Charge-offs	(395)	(15)	(546)	(186)
Recoveries		0	43	1
Provision	247	166	208	2,249
Ending Balance	1,066	2,361	1,066	2,361	1,361
Consumer and Other [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	176	268	191	341	341
Charge-offs	(4)	(26)	(20)	(74)
Recoveries	9	11	21	34
Provision	(30)	2	(41)	(46)
Ending Balance	$ 151	255	$ 151	255	191
Unallocated [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance		20		19	$ 19
Provision		(18)		(17)
Ending Balance		$ 2		$ 2

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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