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Note 10 - Stock Based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		159 Months Ended
	Apr. 01, 2019	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Feb. 20, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)				0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)		4,150		4,150
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price (in dollars per share)		$ 16.63		$ 16.63
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value		$ 63		$ 63
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Nonvested, Number of Shares, Ending Balance (in shares)		0		0
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		$ 0		$ 0
Restricted Stock [Member]
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount		1,100		$ 1,100
Share-Based Payment Arrangement, Expense		$ 261	$ 219
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]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)	40,753
The 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)					675,000