Loans - Major Classifications of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 909,856	$ 714,177
Allowance for loan losses	(8,679)	(6,577)	$ (4,881)
Net discounts	(2,647)	(1,902)
Net deferred loan fees	(1,425)	(1,013)
Net loans	$ 897,105	$ 704,685
Total gross loans percentage	101.50%	101.30%
Allowance for loan losses percentage	(1.00%)	(0.90%)
Net discounts percentage	(0.30%)	(0.30%)
Net deferred loan fees percentage	(0.20%)	(0.10%)
Net loans percentage	100.00%	100.00%
Home Equity Lines of Credit
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 47,410	$ 39,040
Allowance for loan losses	$ (344)	$ (394)
Total gross loans percentage	5.30%	5.50%
Residential Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 237,218	$ 184,926
Total gross loans percentage	26.50%	26.20%
Residential Real Estate \| Closed-end 1-4 family - first lien
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 211,440	$ 162,249
Total gross loans percentage	23.60%	23.00%
Residential Real Estate \| Closed-end 1-4 family - junior lien
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 7,653	$ 5,739
Total gross loans percentage	0.90%	0.80%
Residential Real Estate \| Multi-family
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 18,125	$ 16,938
Total gross loans percentage	2.00%	2.40%
Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 310,019	$ 219,808
Total gross loans percentage	34.60%	31.20%
Commercial Real Estate \| Nonfarm nonresidential
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 288,930	$ 209,391
Total gross loans percentage	32.20%	29.70%
Commercial Real Estate \| Farmland
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 21,089	$ 10,417
Total gross loans percentage	2.40%	1.50%
Construction and Land Development
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 113,526	$ 102,110
Total gross loans percentage	12.70%	14.50%
Construction and Land Development \| Residential
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 53,386	$ 39,680
Total gross loans percentage	6.00%	5.60%
Construction and Land Development \| Other
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 60,140	$ 62,430
Total gross loans percentage	6.70%	8.90%
Commercial Loans
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 161,286	$ 134,426
Allowance for loan losses	$ (1,910)	$ (1,375)	(954)
Total gross loans percentage	17.90%	19.10%
Commercial Loans \| Other commercial loans
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 136,301	$ 112,927
Total gross loans percentage	15.20%	16.00%
Commercial Loans \| Agricultural
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 2,826	$ 1,743
Total gross loans percentage	0.30%	0.20%
Commercial Loans \| State, county, and municipal loans
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 22,159	$ 19,756
Total gross loans percentage	2.40%	2.90%
Consumer Loans
Accounts Notes And Loans Receivable [Line Items]
Total gross loans	$ 40,397	$ 33,867
Allowance for loan losses	$ (425)	$ (326)	$ (217)
Total gross loans percentage	4.50%	4.80%

Loans and leases receivable allowance percentage.

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Loans and leases receivable net deferred loan discounts.

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Percentage of loans and leases receivable gross carrying amount.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance 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 after allowance and 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 and loans held for sale.

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