Allowance for Loans Losses - Summary of Loan Portfolio Individually and Collectively Evaluated for Impairment (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	$ 1,046,380	$ 647,572
Less: Unearned income	(7,200)	(738)
Total	1,039,180	646,834
Commercial and Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	444,718	77,728
Construction, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	49,884	38,039
Construction, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	19,001	26,778
Mortgage, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	272,778	251,824
Mortgage, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	210,679	208,494
Mortgage, Farmland [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	4,176	5,507
Consumer Installment Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	45,144	39,202
Individually Evaluated for Impairment [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	1,449	1,408
Total	1,449	1,408
Individually Evaluated for Impairment [Member] \| Commercial and Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	490	280
Individually Evaluated for Impairment [Member] \| Mortgage, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	335	733
Individually Evaluated for Impairment [Member] \| Mortgage, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	624	395
Collectively Evaluated for Impairment [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	1,044,931	646,164
Less: Unearned income	(7,200)	(738)
Total	1,037,731	645,426
Collectively Evaluated for Impairment [Member] \| Commercial and Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	444,228	77,448
Collectively Evaluated for Impairment [Member] \| Construction, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	49,884	38,039
Collectively Evaluated for Impairment [Member] \| Construction, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	19,001	26,778
Collectively Evaluated for Impairment [Member] \| Mortgage, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	272,443	251,091
Collectively Evaluated for Impairment [Member] \| Mortgage, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	210,055	208,099
Collectively Evaluated for Impairment [Member] \| Mortgage, Farmland [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	4,176	5,507
Collectively Evaluated for Impairment [Member] \| Consumer Installment Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	$ 45,144	$ 39,202

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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