Loans - Non-Accrual Loans, Segregated by Class of Loans (Detail) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Financing Receivable, Nonaccrual	$ 63,704	$ 70,482
Financing Receivable, Nonaccrual, No Allowance	37,057	38,116
Commercial Portfolio Segment [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Financing Receivable, Nonaccrual	20,688	50,659
Financing Receivable, Nonaccrual, No Allowance	11,131	26,693
Commercial and Industrial Total Energy Loans [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Financing Receivable, Nonaccrual	2,218	3,023
Financing Receivable, Nonaccrual, No Allowance	2,218	1,304
Commercial Real Estate Owner Occupied
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Financing Receivable, Nonaccrual	11,838	7,581
Financing Receivable, Nonaccrual, No Allowance	9,039	4,782
Commercial Real Estate Non-Owner Occupied
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Financing Receivable, Nonaccrual	4,453	465
Financing Receivable, Nonaccrual, No Allowance	4,453	465
Construction Loans [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Financing Receivable, Nonaccrual	19,356	1,874
Financing Receivable, Nonaccrual, No Allowance	5,372	202
Total consumer real estate loans [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Financing Receivable, Nonaccrual	4,959	6,615
Financing Receivable, Nonaccrual, No Allowance	4,673	4,486
Consumer Loan [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Financing Receivable, Nonaccrual	192	265
Financing Receivable, Nonaccrual, No Allowance	$ 171	$ 184