Loans - Non-Accrual Loans, Segregated by Class of Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Non-accrual loans	$ 74,987	$ 60,907
Non-accrual with no credit loss allowance	32,376	22,932
Commercial Portfolio Segment [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Non-accrual loans	26,329	19,545
Non-accrual with no credit loss allowance	8,044	5,391
Commercial and Industrial Total Energy Loans [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Non-accrual loans	9,147	11,500
Non-accrual with no credit loss allowance	6,045	7,398
Commercial Real Estate Buildings Land And Other Loans [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Non-accrual loans	33,092	22,420
Non-accrual with no credit loss allowance	14,099	4,983
Construction Loans [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Non-accrual loans	0	0
Non-accrual with no credit loss allowance	0	0
Total consumer real estate loans [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Non-accrual loans	6,419	7,442
Non-accrual with no credit loss allowance	4,188	5,160
Consumer Loan [Member]
Non Accrual Loans Segregated By Class Of Loans [Line Items]
Non-accrual loans	0	0
Non-accrual with no credit loss allowance	$ 0	$ 0