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 expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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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, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	$ 39,919	$ 35,149	$ 37,160	$ 28,511	$ 28,511
Charge-offs	(42)	(666)	(1,580)	(855)
Recoveries	45	167	500	320
Provision	1,346	630	5,188	2,111
Ending Balance	41,268	35,280	41,268	35,280	37,160
ASU 2016-13 [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				897	897
ASU 2016-13 [Member] \| CECL Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				4,296	4,296
Commercial and Agriculture [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	5,348	5,540	7,587	3,011	3,011
Charge-offs		(614)	(1,079)	(754)
Recoveries	15	84	263	131
Provision	(284)	146	(1,692)	2,339
Ending Balance	5,079	5,156	5,079	5,156	7,587
Commercial and Agriculture [Member] \| ASU 2016-13 [Member] \| CECL Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				429	429
Commercial Real Estate Owner Occupied [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	4,328	5,531	4,723	4,565	4,565
Recoveries				0
Provision	37	(50)	(358)	(178)
Ending Balance	4,365	5,481	4,365	5,481	4,723
Commercial Real Estate Owner Occupied [Member] \| ASU 2016-13 [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				19	19
Commercial Real Estate Owner Occupied [Member] \| ASU 2016-13 [Member] \| CECL Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				1,075	1,075
Commercial Real Estate Non Owner Occupied [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	14,421	11,646	12,056	14,138	14,138
Charge-offs			(174)
Recoveries		9	12	25
Provision	126	(100)	2,653	239
Ending Balance	14,547	11,555	14,547	11,555	12,056
Commercial Real Estate Non Owner Occupied [Member] \| ASU 2016-13 [Member] \| CECL Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				(2,847)	(2,847)
Residential Real Estate [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	9,416	6,515	8,489	3,145	3,145
Charge-offs	(1)	(1)	(67)	(12)
Recoveries	19	64	178	118
Provision	1,288	253	2,122	652
Ending Balance	10,722	6,831	10,722	6,831	8,489
Residential Real Estate [Member] \| ASU 2016-13 [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				166	166
Residential Real Estate [Member] \| ASU 2016-13 [Member] \| CECL Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				2,762	2,762
Real Estate Construction [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	3,647	3,447	3,388	2,293	2,293
Recoveries		4	12	13
Provision	69	288	316	(69)
Ending Balance	3,716	3,739	3,716	3,739	3,388
Real Estate Construction [Member] \| ASU 2016-13 [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				0	0
Real Estate Construction [Member] \| ASU 2016-13 [Member] \| CECL Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				1,502	1,502
Farm Real Estate [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	261	243	260	291	291
Provision	(40)	(16)	(39)	(36)
Ending Balance	221	227	221	227	260
Farm Real Estate [Member] \| ASU 2016-13 [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				0	0
Farm Real Estate [Member] \| ASU 2016-13 [Member] \| CECL Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				(28)	(28)
Lease Financing Receivables [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	2,210	1,947	297	429	429
Charge-offs	(15)		(186)
Recoveries			1
Provision	166	(115)	2,249	(975)
Ending Balance	2,361	1,832	2,361	1,832	297
Lease Financing Receivables [Member] \| ASU 2016-13 [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				635	635
Lease Financing Receivables [Member] \| ASU 2016-13 [Member] \| CECL Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				1,743	1,743
Consumer and Other [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	268	272	341
Charge-offs	(26)	(51)	(74)
Recoveries	11	6	34
Provision	2	21	(46)
Ending Balance	255	248	255	248	341
Consumer and Other [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				98	98
Charge-offs				(89)
Recoveries				33
Provision				(72)
Ending Balance		248		248
Consumer and Other [Member] \| ASU 2016-13 [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				77	77
Consumer and Other [Member] \| ASU 2016-13 [Member] \| CECL Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				201	201
Unallocated [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance	20	8	19	541	541
Provision	(18)	203	(17)	211
Ending Balance	$ 2	$ 211	$ 2	211	19
Unallocated [Member] \| ASU 2016-13 [Member] \| CECL Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning Balance				$ (541)	$ (541)