Loans and Allowance for Loan Losses - Summary of Loans Held for Investment (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	$ 995,298	$ 647,572
Less: Unearned income and deferred costs	(4,271)	(738)
Total	991,027	646,834
Commercial and Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	93,286	77,728
Paycheck Protection Program [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	292,068
Construction, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	54,702	38,039
Construction, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	18,040	26,778
Mortgage, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	273,499	251,824
Mortgage, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	213,404	208,494
Mortgage, Farmland [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	3,615	5,507
Consumer Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	$ 46,684	$ 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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