Loans and Allowance for Loan Losses - Summary of Financing Receivable, Past Due (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Past Due [Line Items]
Nonaccrual	$ 4,790	$ 5,530
Total past due and nonaccrual	12,904	10,866
Gross loans	647,572	415,587
Less: Unearned income	(738)	(719)
Total	646,834	414,868
30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	7,120	2,398
60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	625	885
Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Days past due	369	2,053
Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Current loans	633,930	404,002
Less: Unearned income	(738)	(719)
Commercial and Industrial [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	441	312
Total past due and nonaccrual	2,093	621
Gross loans	77,282	49,076
Commercial and Industrial [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	1,652	280
Commercial and Industrial [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due		29
Commercial and Industrial [Member] \| Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Current loans	75,189	48,455
Construction, Commercial [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	929	979
Total past due and nonaccrual	1,749	979
Gross loans	38,039	14,666
Construction, Commercial [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	820
Construction, Commercial [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Current loans	36,290	13,687
Construction, Residential [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Total past due and nonaccrual	241	231
Gross loans	26,778	15,102
Construction, Residential [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	241
Construction, Residential [Member] \| Greater than 90 Days Past Due & Accruing [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due		231
Construction, Residential [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Current loans	26,537	14,871
Mortgage, Commercial [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	1,931	2,441
Total past due and nonaccrual	5,125	3,530
Gross loans	251,824	150,513
Mortgage, Commercial [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	3,194	218
Mortgage, Commercial [Member] \| 60-89 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due		441
Mortgage, Commercial [Member] \| Greater than 90 Days Past Due & Accruing [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due		430
Mortgage, Commercial [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Current loans	246,699	146,983
Mortgage, Residential [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	713	1,441
Total past due and nonaccrual	1,618	3,287
Gross loans	208,494	149,856
Mortgage, Residential [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	319	760
Mortgage, Residential [Member] \| 60-89 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	217	7
Mortgage, Residential [Member] \| Greater than 90 Days Past Due & Accruing [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	369	1,079
Mortgage, Residential [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Current loans	206,876	146,569
Agricultural and Farmland [Member]
Financing Receivable, Past Due [Line Items]
Total past due and nonaccrual		432
Gross loans	5,953	4,395
Agricultural and Farmland [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due		123
Agricultural and Farmland [Member] \| Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Days past due		309
Agricultural and Farmland [Member] \| Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Current loans	5,953	3,963
Consumer Installment Loans [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	776	357
Total past due and nonaccrual	2,078	1,786
Gross loans	39,202	31,979
Consumer Installment Loans [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	894	1,017
Consumer Installment Loans [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	408	408
Consumer Installment Loans [Member] \| Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Days past due		4
Consumer Installment Loans [Member] \| Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Current loans	$ 37,124	$ 30,193

Financing receivable total past due and non accrual.

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Amount of financing receivable not past due.

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Amount of financing receivable on nonaccrual status.

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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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