Loans and ACL - Summary of Aging of loans held for investment by loan category (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Financing Receivable, Past Due [Line Items]
Days past due	$ 1,977,738	$ 2,110,755
Nonaccrual	22,106	22,957
Deferred costs, net of loan fees	847	1,042
Total	1,978,585	2,111,797
Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	22,106	22,957
Nonaccrual loans with no allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	3,085	2,447
Non accrual loans with an allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	19,021	20,510
30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total	3,722	7,130
60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total	7,061	2,041
Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Total	1,881	2,486
Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	1,943,815	2,077,183
Deferred costs, net of loan fees	847	1,042
Commercial and Industrial [Member]
Financing Receivable, Past Due [Line Items]
Days past due	323,976	354,904
Nonaccrual	9,160	10,185
Commercial and Industrial [Member] \| Nonaccrual loans with no allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	353	778
Commercial and Industrial [Member] \| Non accrual loans with an allowance
Financing Receivable, Past Due [Line Items]
Nonaccrual	8,807	9,407
Commercial and Industrial [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	1,049	1,335
Commercial and Industrial [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	1,042	1,232
Commercial and Industrial [Member] \| Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Days past due	1,643	2,259
Commercial and Industrial [Member] \| Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	311,082	339,893
Construction, Commercial [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	78,476	114,491
Nonaccrual		220
Construction, Commercial [Member] \| Non accrual loans with an allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual		220
Construction, Commercial [Member] \| 60-89 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due		33
Construction, Commercial [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	78,476	114,238
Construction, Residential [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	52,031	51,807
Construction, Residential [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	154
Construction, Residential [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	51,877	51,807
Commercial [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	810,978	847,842
Nonaccrual	4,033	4,235
Commercial [Member] \| Nonaccrual loans with no allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	1,125
Commercial [Member] \| Non accrual loans with an allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	2,908	4,235
Commercial [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	511	625
Commercial [Member] \| 60-89 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	3,073
Commercial [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	803,361	842,982
Residential [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	671,317	692,253
Nonaccrual	8,244	7,497
Residential [Member] \| Nonaccrual loans with no allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	1,607	1,669
Residential [Member] \| Non accrual loans with an allowance \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	6,637	5,828
Residential [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	930	3,874
Residential [Member] \| 60-89 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	2,745	476
Residential [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	659,398	680,406
Farmland [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	4,723	5,520
Farmland [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	4,723	5,520
Consumer [Member]
Financing Receivable, Past Due [Line Items]
Days past due	36,237	43,938
Nonaccrual	669	820
Consumer [Member] \| Non accrual loans with an allowance
Financing Receivable, Past Due [Line Items]
Nonaccrual	669	820
Consumer [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	1,078	1,296
Consumer [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	201	300
Consumer [Member] \| Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Days past due	238	227
Consumer [Member] \| Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable Recorded Investments Current	$ 34,051	$ 41,295