Loans - Summary of Financing Receivable, Past Due (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
Nonaccrual	$ 4,249	$ 4,790
Total Past Due & Nonaccrual	8,276	12,904
Gross loans	671,666	647,572
Less: Unearned income	(731)	(738)
Total	670,935	646,834
30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	2,388	7,120
60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	767	625
Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Days past due	872	369
Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Current Loans	662,659	633,930
Less: Unearned income	(731)	(738)
Commercial and Industrial [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	428	441
Total Past Due & Nonaccrual	574	2,093
Gross loans	82,177	77,282
Commercial and Industrial [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	123	1,652
Commercial and Industrial [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	23
Commercial and Industrial [Member] \| Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Current Loans	81,603	75,189
Construction, Commercial [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	917	929
Total Past Due & Nonaccrual	917	1,749
Gross loans	42,527	38,039
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	41,610	36,290
Construction, Residential [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Total Past Due & Nonaccrual	589	241
Gross loans	27,152	26,778
Construction, Residential [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	589	241
Construction, Residential [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Current Loans	26,563	26,537
Mortgage, Commercial [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	1,472	1,931
Total Past Due & Nonaccrual	1,859	5,125
Gross loans	256,543	251,824
Mortgage, Commercial [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due		3,194
Mortgage, Commercial [Member] \| 60-89 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	387
Mortgage, Commercial [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Current Loans	254,684	246,699
Mortgage, Residential [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	709	713
Total Past Due & Nonaccrual	2,424	1,618
Gross loans	215,155	208,494
Mortgage, Residential [Member] \| 30-59 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	871	319
Mortgage, Residential [Member] \| 60-89 Days Past Due [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	39	217
Mortgage, Residential [Member] \| Greater than 90 Days Past Due & Accruing [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Days past due	805	369
Mortgage, Residential [Member] \| Current Loans [Member] \| Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Current Loans	212,731	206,876
Agricultural and Farmland [Member]
Financing Receivable, Past Due [Line Items]
Gross loans	5,703	5,953
Agricultural and Farmland [Member] \| Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Current Loans	5,703	5,953
Consumer Installment Loans [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual	723	776
Total Past Due & Nonaccrual	1,913	2,078
Gross loans	42,409	39,202
Consumer Installment Loans [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	805	894
Consumer Installment Loans [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Days past due	318	408
Consumer Installment Loans [Member] \| Greater than 90 Days Past Due & Accruing [Member]
Financing Receivable, Past Due [Line Items]
Days past due	67
Consumer Installment Loans [Member] \| Current Loans [Member]
Financing Receivable, Past Due [Line Items]
Current Loans	$ 40,496	$ 37,124

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Amount of financing receivable not past due.

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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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