Allowance for Credit Losses - Aging Analysis of Past Due Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$ 3,229,667	$ 3,270,046
Past Due 90 Days and Accruing	229	462
30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	9,682	16,263
60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	2,172	3,145
90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	10,688	4,109
Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	22,542	23,517
Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,207,125	3,246,529
Commercial and Agriculture [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	310,400	308,692
Commercial and Agriculture [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	827	382
Commercial and Agriculture [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	405	239
Commercial and Agriculture [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	253	141
Commercial and Agriculture [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,485	762
Commercial and Agriculture [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	308,915	307,930
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	390,786	385,547
Past Due 90 Days and Accruing		23
Commercial Real Estate Owner Occupied [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	176	179
Commercial Real Estate Owner Occupied [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	140	6
Commercial Real Estate Owner Occupied [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	316	185
Commercial Real Estate Owner Occupied [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	390,470	385,362
Commercial Real Estate Non Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,232,781	1,239,017
Commercial Real Estate Non Owner Occupied [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,436	8,332
Commercial Real Estate Non Owner Occupied [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	389
Commercial Real Estate Non Owner Occupied [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	8,496	1,130
Commercial Real Estate Non Owner Occupied [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	10,321	9,462
Commercial Real Estate Non Owner Occupied [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,222,460	1,229,555
Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	943,425	944,328
Past Due 90 Days and Accruing		104
Residential Real Estate [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	6,380	5,954
Residential Real Estate [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,362	1,629
Residential Real Estate [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,672	2,331
Residential Real Estate [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	9,414	9,914
Residential Real Estate [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	934,011	934,414
Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	254,254	285,137
Real Estate Construction [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	254,254	285,137
Farm Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,700	37,775
Farm Real Estate [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,700	37,775
Lease Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,693	35,103
Past Due 90 Days and Accruing	229	335
Lease Financing Receivable [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	770	1,301
Lease Financing Receivable [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans		1,240
Lease Financing Receivable [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	105	454
Lease Financing Receivable [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	875	2,995
Lease Financing Receivable [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	31,818	32,108
Consumer and Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,628	34,447
Consumer and Other [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	93	115
Consumer and Other [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	16	37
Consumer and Other [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	22	47
Consumer and Other [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	131	199
Consumer and Other [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$ 32,497	$ 34,248