Loans and Allowance For Loan Losses - Summary of Financing Receivable and Related Impairment Methodology (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	$ 1,352,639	$ 1,369,070
Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	425,643	414,548
Real Estate Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	41,558	37,193
SBA [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	204,734	317,564
Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	64,253	49,075
Loans Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	2,397	2,977
Loans collectively evaluated for impairment	1,350,242	1,366,093
Total gross loans	1,352,639	1,369,070
Loans individually evaluated for impairment	19	300
Loans collectively evaluated for impairment	13,221	13,811
Total allowance for loan losses	13,240	14,111
Loans Receivable [Member] \| Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	1,163	2,288
Loans collectively evaluated for impairment	424,480	412,260
Total gross loans	425,643	414,548
Loans individually evaluated for impairment	19	41
Loans collectively evaluated for impairment	8,114	8,882
Total allowance for loan losses	8,133	8,923
Loans Receivable [Member] \| Real Estate - Other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	1,000
Loans collectively evaluated for impairment	615,451	550,690
Total gross loans	616,451	550,690
Loans collectively evaluated for impairment	4,069	3,877
Total allowance for loan losses	4,069	3,877
Loans Receivable [Member] \| Real Estate Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collectively evaluated for impairment	41,558	37,193
Total gross loans	41,558	37,193
Loans collectively evaluated for impairment	697	681
Total allowance for loan losses	697	681
Loans Receivable [Member] \| SBA [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	234	689
Loans collectively evaluated for impairment	204,500	316,875
Total gross loans	204,734	317,564
Loans individually evaluated for impairment	0	259
Loans collectively evaluated for impairment	317	345
Total allowance for loan losses	317	604
Loans Receivable [Member] \| Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collectively evaluated for impairment	64,253	49,075
Total gross loans	64,253	49,075
Loans collectively evaluated for impairment	24	26
Total allowance for loan losses	$ 24	$ 26

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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