Commitments and Contingent Liabilities - Notional Amount of Outstanding Commitments (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Commitments to extend credit [Member]
Loss Contingencies [Line Items]
Financial instrument of credit risk	$ 2,478,090	$ 2,356,539
Financial standby letters of credit [Member]
Loss Contingencies [Line Items]
Financial instrument of credit risk	19,676	18,417
Performance standby letters of credit [Member]
Loss Contingencies [Line Items]
Financial instrument of credit risk	13,401	12,853
Commercial letters of credit [Member]
Loss Contingencies [Line Items]
Financial instrument of credit risk	$ 886	$ 573