Loans and Allowance For Loan Losses - Summary of Financing Receivable and Related Impairment Methodology (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	$ 1,376,649	$ 1,369,070
Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	474,281	414,548
Real estate - construction and land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	43,194	37,193
SBA [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	81,403	317,564
Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	80,559	49,075
Loans Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	731	2,977
Loans collectively evaluated for impairment	1,375,918	1,366,093
Total gross loans	1,376,649	1,369,070
Loans individually evaluated for impairment	142	300
Loans collectively evaluated for impairment	13,939	13,811
Total allowance for loan losses	14,081	14,111
Loans Receivable [Member] \| Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	0	2,288
Loans collectively evaluated for impairment	474,281	412,260
Total gross loans	474,281	414,548
Loans individually evaluated for impairment	0	41
Loans collectively evaluated for impairment	8,552	8,882
Total allowance for loan losses	8,552	8,923
Loans Receivable [Member] \| Real estate - other [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment		0
Loans collectively evaluated for impairment	697,212	550,690
Total gross loans	697,212	550,690
Loans collectively evaluated for impairment	4,524	3,877
Total allowance for loan losses	4,524	3,877
Loans Receivable [Member] \| Real estate - construction and land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collectively evaluated for impairment	43,194	37,193
Total gross loans	43,194	37,193
Loans collectively evaluated for impairment	681	681
Total allowance for loan losses	681	681
Loans Receivable [Member] \| SBA [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	731	689
Loans collectively evaluated for impairment	80,672	316,875
Total gross loans	81,403	317,564
Loans individually evaluated for impairment	142	259
Loans collectively evaluated for impairment	167	345
Total allowance for loan losses	309	604
Loans Receivable [Member] \| Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collectively evaluated for impairment	80,559	49,075
Total gross loans	80,559	49,075
Loans collectively evaluated for impairment	15	26
Total allowance for loan losses	$ 15	$ 26

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

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