Note 13 - Stock-based Compensation (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Feb. 20, 2018
Proceeds from Stock Options Exercised	$ 89,000	$ 43,000	$ 688,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	96,000	42,000	616,000
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 0	$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)	0	0	0
Regular Quarterly Retainer of Vested Restricted Stock	$ 10,000	$ 10,000	$ 7,500
Monthly Meeting Fees Director Could Receive in Cash	800	800	725
Monthly Meeting Fees Director Could Receive in Vested Restricted Stock	1,000	1,000	900
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense	0	0
Restricted Stock [Member]
Share-based Payment Arrangement, Expense	749,000	672,000	915,000
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	782,000	797,000	751,000
Restricted Stock [Member] \| Director [Member]
Share-based Payment Arrangement, Expense	$ 683,000	$ 779,000	$ 626,000
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period (in shares)	20,474	27,986	17,373
Restricted Stock [Member] \| Minimum [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Month)	12 months
Restricted Stock [Member] \| Maximum [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Month)	36 months
Restricted Stock [Member] \| Cliff Vested [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Month)	36 months
HomeTown Bankshares Corporation [Member]
Stock or Unit Option Plan Expense			$ 147,000
HomeTown Bankshares Corporation [Member] \| Restricted Stock [Member]
Share-based Payment Arrangement, Expense			$ 257,000
The 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)				675,000

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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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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Gross number of share options (or share units) granted during the period.

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Amount of noncash expense for option under share-based payment arrangement.

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