Off-Balance Sheet Commitments - Distribution of Total Loan Commitments (Detail) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Loss Contingencies [Line Items]
Total commitments	$ 1,169,410	$ 1,098,954
Unused Commitments to Extend Credit
Loss Contingencies [Line Items]
Total commitments	946,544	930,122
Standby letters of credit
Loss Contingencies [Line Items]
Total commitments	205,160	163,071
Commercial letters of credit
Loss Contingencies [Line Items]
Total commitments	$ 17,706	$ 5,761

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details