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Note 1 - Basis of Presentation (Details Textual)			3 Months Ended
Note 1 - Basis of Presentation (Details Textual)	Jan. 01, 2023 USD ($)	Dec. 01, 2022 USD ($) shares	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss			$ 0
Retained Earnings (Accumulated Deficit)			93,024,000		$ 94,154,000
Financing Receivable, Credit Loss, Expense (Reversal)			507,000	$ 0
Provision for Loan, Lease, and Other Losses			334,000	$ 0
Accounting Standards Update 2016-13 [Member]
Financing Receivable, Credit Loss, Expense (Reversal)			507,000
Provision for Loan, Lease, and Other Losses			334,000
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase	$ 121,000
Accounting Standards Update 2016-13 [Member] \| Unfunded Loan Commitment [Member]
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)			173,000
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	5,300,000
Retained Earnings (Accumulated Deficit)	4,400,000
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Unfunded Loan Commitment [Member]
Off-Balance-Sheet, Credit Loss, Liability	622,000
Retained Earnings (Accumulated Deficit)	491,000
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Loans [Member]
Retained Earnings (Accumulated Deficit)	$ 3,900,000
Commercial Portfolio Segment [Member] \| Minimum [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process			150,000
Accrued Interest Receivable and Other Assets [Member]
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss			1,600,000
Interest Receivable			$ 4,300,000
LBSI Insurance, LLC [Member]
Business Acquisition, Percentage of Voting Interests Acquired		100.00%
Liberty Bancshares Inc [Member]
Business Combination, Amount Shares Issued to Acquiree's Shareholders Per Share (in shares) \| shares		2.752
Stock Issued During Period, Shares, Acquisitions (in shares) \| shares		2,561,513
Business Combination, Consideration Transferred		$ 73,265,000
Number of Branches		6