Loans and Allowance For Credit Losses - Schedule of Amortized Cost of Individually Evaluated Loans by Type of Collateral (Detail) - Loans Receivable [Member] - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	$ 9,236	$ 3,781
SBA [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	451	53
Commercial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	8,785	3,728
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	451	53
Residential Real Estate [Member] \| SBA [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	451	53
Residential Real Estate [Member] \| Commercial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	0	0
Business Assets [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	8,785	3,728
Business Assets [Member] \| SBA [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	0	0
Business Assets [Member] \| Commercial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual	$ 8,785	$ 3,728

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