Credit Quality - Schedule of Nonaccrual Loans, Segregated by Class of Loans and Leases (Detail) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Financing Receivable, Past Due [Line Items]
Nonaccruals	$ 99,301	$ 96,492
With No Related Allowance for Credit Losses	94,012	94,029
Other Commercial [Member]
Financing Receivable, Past Due [Line Items]
Nonaccruals	6,888	5,978
With No Related Allowance for Credit Losses	4,424	3,515
Residential Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccruals	16,658	15,423
With No Related Allowance for Credit Losses	14,371	15,423
Owner-Occupied [Member] \| Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccruals	1,216	1,749
With No Related Allowance for Credit Losses	1,216	1,749
Nonowner-Occupied [Member] \| Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccruals	71,212	71,038
With No Related Allowance for Credit Losses	71,212	71,038
Construction & land development [Member]
Financing Receivable, Past Due [Line Items]
Nonaccruals	2,687	1,301
With No Related Allowance for Credit Losses	2,149	1,301
Bankcard [Member] \| Consumer [Member]
Financing Receivable, Past Due [Line Items]
Nonaccruals	0	0
With No Related Allowance for Credit Losses	0	0
Other Consumer [Member] \| Consumer [Member]
Financing Receivable, Past Due [Line Items]
Nonaccruals	640	1,003
With No Related Allowance for Credit Losses	$ 640	$ 1,003