Loans - Summary of Loans Held for Investment (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

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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