Loans Held-for-Investment and Allowance for Credit Losses - Loans Held-for-Investment by Class of Financing Receivables (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024	Jun. 30, 2024
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 8,074,944	$ 7,913,098	$ 7,519,733
Less-Allowance for credit losses	(102,792)	(98,325)	(95,170)
Net loans held-for-investment	7,972,152	7,814,773	7,424,563
C&I [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	1,202,151	1,176,993	1,141,990
Municipal [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	306,140	369,246	359,124
Construction & Development [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	1,172,834	1,054,603	986,394
Farm [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	302,969	339,665	318,597
Non-Owner Occupied CRE [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	746,341	805,566	815,713
Owner Occupied CRE [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	1,124,610	1,083,100	1,049,715
Residential [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	2,286,220	2,196,767	1,990,604
Auto [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	698,897	638,560	615,192
Non-Auto [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	148,649	153,055	156,218
Commercial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	1,508,291	1,546,239	1,501,114
Commercial [Member] | C&I [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	1,202,151	1,176,993	1,141,990
Commercial [Member] | Municipal [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	306,140	369,246	359,124
Agriculture [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	86,133	95,543	86,186
Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	5,632,974	5,479,701	5,161,023
Real Estate [Member] | Construction & Development [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	1,172,834	1,054,603	986,394
Real Estate [Member] | Farm [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	302,969	339,665	318,597
Real Estate [Member] | Non-Owner Occupied CRE [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	746,341	805,566	815,713
Real Estate [Member] | Owner Occupied CRE [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	1,124,610	1,083,100	1,049,715
Real Estate [Member] | Residential [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	2,286,220	2,196,767	1,990,604
Consumer [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	847,546	791,615	771,410
Net loans held-for-investment	7,972,152	7,814,773	7,424,563
Consumer [Member] | Auto [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	698,897	638,560	615,192
Consumer [Member] | Non-Auto [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 148,649	$ 153,055	$ 156,218