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Note 1 - Business and Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jan. 01, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Number of Reportable Segments	1
Financing Receivable, after Allowance for Credit Loss, Total	$ 1,044,612	$ 1,232,389
Equity Securities, FV-NI, Total	$ 0	0
Loans and Leases Receivable, Days Before Nonaccrual Status (Day)	90 days
Loans and Leases Receivable, Certain Consumer Loans and Auto Receivables, Days Before Chargeoff (Day)	120 days
Financing Receivable, Allowance for Credit Loss, Ending Balance	$ 23,514	23,854		$ 19,484	$ 21,351
Reserve for Unfunded Commitments			$ 2,160
Retained Earnings (Accumulated Deficit), Ending Balance	$ 306,395	264,356
Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss, Ending Balance			2,017
Retained Earnings (Accumulated Deficit), Ending Balance			52
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	15 years
Land and Land Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	20 years
Land and Land Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	50 years
Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	20 years
Unfunded Loan Commitment [Member] \| Accounting Standards Update 2016-13 [Member]
Reserve for Unfunded Commitments			$ (2,107)
Commercial Portfolio Segment [Member]
Financing Receivable, Loan Deferrals	$ 84,000
Financing Receivable, Allowance for Credit Loss, Ending Balance	6,966	$ 9,205		$ 4,959	$ 6,311
Commercial Portfolio Segment [Member] \| Paycheck Protection Program Loans [Member]
Financing Receivable, after Allowance for Credit Loss, Total	$ 46,000