Allowance for Credit Losses - Aging Analysis of Past Due Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$ 3,151,124	$ 3,081,230
Past Due 90 Days and Accruing	223	225
30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	2,095	7,154
60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,262	10,136
90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	4,676	7,298
Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	8,033	24,588
Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,143,091	3,056,642
Commercial and Agriculture [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	338,598	328,488
Past Due 90 Days and Accruing	98
Commercial and Agriculture [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	114	825
Commercial and Agriculture [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	0	114
Commercial and Agriculture [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,639	1,374
Commercial and Agriculture [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,753	2,313
Commercial and Agriculture [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	336,845	326,175
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	378,248	374,367
Past Due 90 Days and Accruing		225
Commercial Real Estate Owner Occupied [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,231
Commercial Real Estate Owner Occupied [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	7	225
Commercial Real Estate Owner Occupied [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,238	225
Commercial Real Estate Owner Occupied [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	377,010	374,142
Commercial Real Estate Non Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,263,612	1,225,991
Commercial Real Estate Non Owner Occupied [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans		69
Commercial Real Estate Non Owner Occupied [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	0	8,000
Commercial Real Estate Non Owner Occupied [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	484	2,514
Commercial Real Estate Non Owner Occupied [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	484	10,583
Commercial Real Estate Non Owner Occupied [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,263,128	1,215,408
Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	815,408	763,869
Residential Real Estate [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	426	5,504
Residential Real Estate [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,262	1,634
Residential Real Estate [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,602	2,273
Residential Real Estate [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,290	9,411
Residential Real Estate [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	812,118	754,458
Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	277,643	305,992
Real Estate Construction [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	277,643	305,992
Farm Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	23,866	23,035
Farm Real Estate [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	23,866	23,035
Lease Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	42,758	46,900
Past Due 90 Days and Accruing	125
Lease Financing Receivable [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	255	575
Lease Financing Receivable [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	0	351
Lease Financing Receivable [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	924	909
Lease Financing Receivable [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,179	1,835
Lease Financing Receivable [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	41,579	45,065
Consumer and Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	10,991	12,588
Consumer and Other [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	69	181
Consumer and Other [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	0	37
Consumer and Other [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	20	3
Consumer and Other [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	89	221
Consumer and Other [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$ 10,902	$ 12,367