Loans and Allowance For Credit Losses - Summary of Financing Receivable and Related Impairment Methodology (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	$ 1,301,972	$ 1,369,070
Commercial And Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	428,169	414,548
Real Estate Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	41,312	37,193
SBA [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	107,096	317,564
Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	61,193	49,075
Loans Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	1,233	2,977
Loans collectively evaluated for impairment	1,300,739	1,366,093
Total gross loans	1,301,972	1,369,070
Loans individually evaluated for impairment	0	300
Loans collectively evaluated for impairment	13,571	13,811
Total allowance for loan losses	13,571	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	428,169	412,260
Total gross loans	428,169	414,548
Loans individually evaluated for impairment	0	41
Loans collectively evaluated for impairment	8,209	8,882
Total allowance for loan losses	8,209	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	663,202	550,690
Total gross loans	664,202	550,690
Loans collectively evaluated for impairment	4,393	3,877
Total allowance for loan losses	4,393	3,877
Loans Receivable [Member] \| Real Estate Construction & Land [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collectively evaluated for impairment	41,312	37,193
Total gross loans	41,312	37,193
Loans collectively evaluated for impairment	675	681
Total allowance for loan losses	675	681
Loans Receivable [Member] \| SBA [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans individually evaluated for impairment	233	689
Loans collectively evaluated for impairment	106,863	316,875
Total gross loans	107,096	317,564
Loans individually evaluated for impairment	0	259
Loans collectively evaluated for impairment	273	345
Total allowance for loan losses	273	604
Loans Receivable [Member] \| Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collectively evaluated for impairment	61,193	49,075
Total gross loans	61,193	49,075
Loans collectively evaluated for impairment	21	26
Total allowance for loan losses	$ 21	$ 26

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

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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