Loans and Allowance For Loan Losses - Summary of Aging Analysis of the Loan Portfolio by the Time Past Due (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Total	$ 1,470,313	$ 1,369,070
Commercial And Industrial [Member]
Financing Receivable, Past Due [Line Items]
Total	439,044	414,548
Real Estate - Construction & Land [Member]
Financing Receivable, Past Due [Line Items]
Total	45,550	37,193
SBA [Member]
Financing Receivable, Past Due [Line Items]
Total	364,273	317,564
Other Loans [Member]
Financing Receivable, Past Due [Line Items]
Total	47,926	49,075
Loans Receivable [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	234	234
Current	1,468,330	1,367,331
Total	1,470,313	1,369,070
Loans Receivable [Member] | Over 30 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	1,749	1,505
Loans Receivable [Member] | Commercial And Industrial [Member]
Financing Receivable, Past Due [Line Items]
Current	438,295	414,548
Total	439,044	414,548
Loans Receivable [Member] | Commercial And Industrial [Member] | Over 30 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	749
Loans Receivable [Member] | Real Estate - Other [Member]
Financing Receivable, Past Due [Line Items]
Current	572,520	549,185
Total	573,520	550,690
Loans Receivable [Member] | Real Estate - Other [Member] | Over 30 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	1,000	1,505
Loans Receivable [Member] | Real Estate - Construction & Land [Member]
Financing Receivable, Past Due [Line Items]
Current	45,550	37,193
Total	45,550	37,193
Loans Receivable [Member] | SBA [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	234	234
Current	364,039	317,330
Total	364,273	317,564
Loans Receivable [Member] | Other Loans [Member]
Financing Receivable, Past Due [Line Items]
Current	47,926	49,075
Total	$ 47,926	$ 49,075