Allowance for Credit Losses - Aging Analysis of Past Due Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$ 3,254,904	$ 3,270,046
Past Due 90 Days and Accruing	103	462
30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	2,040	16,263
60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	2,285	3,145
90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	13,853	4,109
Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	18,178	23,517
Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,236,726	3,246,529
Commercial and Agriculture [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	315,479	308,692
Commercial and Agriculture [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	151	382
Commercial and Agriculture [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	75	239
Commercial and Agriculture [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	477	141
Commercial and Agriculture [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	703	762
Commercial and Agriculture [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	314,776	307,930
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	389,434	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		179
Commercial Real Estate Owner Occupied [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	7	6
Commercial Real Estate Owner Occupied [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	7	185
Commercial Real Estate Owner Occupied [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	389,427	385,362
Commercial Real Estate Non Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,229,731	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	472	8,332
Commercial Real Estate Non Owner Occupied [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	9,900	1,130
Commercial Real Estate Non Owner Occupied [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	10,372	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	1,219,359	1,229,555
Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	957,960	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	1,149	5,954
Residential Real Estate [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,741	1,629
Residential Real Estate [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,339	2,331
Residential Real Estate [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	6,229	9,914
Residential Real Estate [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	951,731	934,414
Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	265,488	285,137
Real Estate Construction [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	265,488	285,137
Farm Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,440	37,775
Farm Real Estate [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,440	37,775
Lease Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,665	35,103
Past Due 90 Days and Accruing	103	335
Lease Financing Receivable [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	211	1,301
Lease Financing Receivable [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	464	1,240
Lease Financing Receivable [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	103	454
Lease Financing Receivable [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	778	2,995
Lease Financing Receivable [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	31,887	32,108
Consumer and Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	31,707	34,447
Consumer and Other [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	57	115
Consumer and Other [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	5	37
Consumer and Other [Member] \| 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	27	47
Consumer and Other [Member] \| Financial Asset, Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	89	199
Consumer and Other [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$ 31,618	$ 34,248