Loans and ACL - Summary of Aging of loans held for investment by loan category (Detail) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Financing Receivable, Past Due [Line Items]
Days past due	$ 1,852,003	$ 1,864,512
Nonaccrual	28,629	20,605
Deferred costs, net of loan fees	1,458	1,205
Total	1,853,461	1,865,717
Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	28,629	20,605
Nonaccrual loans with no allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	6,190	9,010
Non accrual loans with an allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	22,439	11,595
30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total	4,674	12,076
60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total	4,099	2,119
Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Total	2,551	3,158
Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	1,813,508	1,827,759
Deferred costs, net of loan fees	1,458	1,205
Commercial and Industrial [Member]
Financing Receivable, Past Due [Line Items]
Days past due	276,589	282,745
Nonaccrual	16,964	6,639
Commercial and Industrial [Member] \| Nonaccrual loans with no allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	1,700	1,774
Commercial and Industrial [Member] \| Non accrual loans with an allowance
Financing Receivable, Past Due [Line Items]
Nonaccrual	15,264	4,865
Commercial and Industrial [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	1,506	1,099
Commercial and Industrial [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	1,442	780
Commercial and Industrial [Member] \| Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Days past due	841	1,508
Commercial and Industrial [Member] \| Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	255,836	272,719
Construction, Commercial [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	54,611	51,738
Nonaccrual	62	236
Construction, Commercial [Member] \| Non accrual loans with an allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	62	236
Construction, Commercial [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	3	62
Construction, Commercial [Member] \| 60-89 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	61	43
Construction, Commercial [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	54,485	51,397
Construction, Residential [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	28,844	31,772
Construction, Residential [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	28,844	31,772
Commercial [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	823,378	824,721
Nonaccrual	1,166	5,651
Commercial [Member] \| Nonaccrual loans with no allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	698	5,634
Commercial [Member] \| Non accrual loans with an allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	468	17
Commercial [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	1,101	49
Commercial [Member] \| 60-89 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	10
Commercial [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	821,101	819,021
Residential [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	636,830	636,743
Nonaccrual	9,338	7,379
Residential [Member] \| Nonaccrual loans with no allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	3,792	1,602
Residential [Member] \| Non accrual loans with an allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	5,546	5,777
Residential [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	1,143	9,840
Residential [Member] \| 60-89 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	2,407	1,006
Residential [Member] \| Greater than 90 Days Past Due & Accruing [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	1,595	1,575
Residential [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	622,347	616,943
Farmland [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	4,368	4,580
Farmland [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	4,368	4,580
Consumer [Member]
Financing Receivable, Past Due [Line Items]
Days past due	27,383	32,213
Nonaccrual	1,099	700
Consumer [Member] \| Non accrual loans with an allowance
Financing Receivable, Past Due [Line Items]
Nonaccrual	1,099	700
Consumer [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	921	1,026
Consumer [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	179	290
Consumer [Member] \| Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Days past due	115	75
Consumer [Member] \| Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	$ 25,069	$ 30,122