Refers to the maximum vesting period of granted restricted stock.

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Refers to the amount of monthly meeting fees that a director could receive if restricted stock vested.

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Refers to the amount of monthly meeting fees that a director could receive in cash.

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Refers to the amount of regular quarterly retainer if restricted stock vested.

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Stock Options Acquired from Acquisition

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Amount of increase to additional paid-in capital (APIC) for recognition of cost for restricted stock unit under share-based payment arrangement.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Number of shares authorized for issuance under share-based payment arrangement.

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Number of shares issued under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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Stock Based Compensation - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	May 15, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of common stock authorizes for issuance (in shares)				675,000
Business combinations options acquired (in shares)	40,753
Unrecognized compensation expense	$ 0
Regular quarterly board retainer if restricted stock vested	7,500
Monthly meeting fees a director could receive in cash	725
Monthly meeting fees a director could receive if restricted stock vested	$ 900
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum vesting period of granted restricted stock	36 months
Unrecognized compensation expense	$ 902,000		$ 647,000
Weighted average period for recognition of unrecognized compensation cost	1 year 6 months
Share based compensation expense	$ 737,000	$ 437,000
Number of shares issued (in shares)	13,128	10,865
Recognized share based compensation expense	$ 467,000	$ 422,000
Restricted Stock \| Vesting 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of remainder of restricted stock vesting each year	33.33%
Restricted Stock \| Vesting 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of remainder of restricted stock vesting each year	33.33%
Restricted Stock \| Vesting 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of remainder of restricted stock vesting each year	33.33%
HomeTown Bankshares Corporation Merger \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Business combinations options acquired (in shares)	40,753
HomeTown Bankshares Corporation Merger \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation expense	$ 257,000