Loans and Allowance for Loan Losses - Summary of Loan Portfolio Individually and Collectively Evaluated for Impairment (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	$ 647,572	$ 415,587
Less: Unearned income	(738)	(719)
Total	646,834	414,868
Commercial and Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	77,282	49,076
Agricultural [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	446	216
Construction, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	38,039	14,666
Construction, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	26,778	15,102
Mortgage, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	251,824	150,513
Mortgage, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	208,494	149,856
Mortgage, Farmland [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	5,507	4,179
Consumer Installment Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	39,202	31,979
Individually Evaluated for Impairment [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	1,408	1,946
Total	1,408	1,946
Individually Evaluated for Impairment [Member] \| Commercial and Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	280
Individually Evaluated for Impairment [Member] \| Mortgage, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	733	1,258
Individually Evaluated for Impairment [Member] \| Mortgage, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	395	688
Collectively Evaluated for Impairment [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	646,164	413,641
Less: Unearned income	(738)	(719)
Total	645,426	412,922
Collectively Evaluated for Impairment [Member] \| Commercial and Industrial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	77,002	49,076
Collectively Evaluated for Impairment [Member] \| Agricultural [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	446	216
Collectively Evaluated for Impairment [Member] \| Construction, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	38,039	14,666
Collectively Evaluated for Impairment [Member] \| Construction, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	26,778	15,102
Collectively Evaluated for Impairment [Member] \| Mortgage, Commercial [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	251,091	149,255
Collectively Evaluated for Impairment [Member] \| Mortgage, Residential [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	208,099	149,168
Collectively Evaluated for Impairment [Member] \| Mortgage, Farmland [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	5,507	4,179
Collectively Evaluated for Impairment [Member] \| Consumer Installment Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Gross loans	$ 39,202	$ 31,979

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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