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Note 1 - Nature of Banking Activities and Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands			12 Months Ended
	Sep. 30, 2021	Jul. 01, 2021	Dec. 31, 2022	Dec. 31, 2021	Jan. 01, 2023
Financing Receivable, Deferred Payments			$ 0
Financing Receivable, Troubled Debt Restructuring			101	$ 1,600
Advertising Expense			455	487
Business Combination, Consideration Transferred, Total			117,566
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Total			352,449
Retained Earnings (Accumulated Deficit), Total			$ 90,284	76,990
Subsequent Event [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member]
Retained Earnings (Accumulated Deficit), Total					$ 1,600
Minimum [Member]
Amount of Substandard and Doubtful Loans Evaluated as Impaired				$ 250
Minimum [Member] | Core Deposits [Member]
Finite-Lived Intangible Asset, Useful Life (Year)			6 years
Minimum [Member] | Premises and Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)			3 years
Minimum [Member] | Software and Software Development Costs [Member]
Property, Plant and Equipment, Useful Life (Year)			3 years
Maximum [Member] | Core Deposits [Member]
Finite-Lived Intangible Asset, Useful Life (Year)			10 years
Maximum [Member] | Premises and Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)			40 years
Maximum [Member] | Software and Software Development Costs [Member]
Property, Plant and Equipment, Useful Life (Year)			7 years
Fincastle and SmartBank [Member]
Financing Receivable, Purchased with Credit Deterioration, Amount at Purchase Price, Total			$ 0
The Bank of Fincastle [Member]
Business Combination, Consideration Transferred, Total		$ 33,821
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Total		$ 270,497
Smartbank [Member]
Business Combination, Consideration Transferred, Total	$ 83,745
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Total	$ 81,952

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