Note 3 - Loans and Allowance for Credit Losses (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Financing Receivable, Allowance for Credit Loss, Ending Balance	$ 23,514	$ 23,854	$ 19,484	$ 21,351
Loans and Leases Receivable, Nonaccrual, Commitment to Lend	$ 0	$ 0
Troubled Debt Restructurings During Period	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 0	$ 0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Financing Receivable, Troubled Debt Restructuring	$ 1,965	$ 6,221
Financing Receivable, Held-for-Sale	0	0
Other Real Estate, Ending Balance	0	0
Mortgage Loans in Process of Foreclosure, Amount	247	346
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss, Ending Balance	6,529	5,660	4,064	3,884
Financing Receivable, Troubled Debt Restructuring	$ 1,793	6,040
Allowance for Credit Losses, Collateral-dependent Loans		$ 0
Number of Collateral-dependent Loans	5	5
Collateral-dependent Loans, Balance	$ 8,400	$ 11,100
Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss, Ending Balance	9,972	8,936	6,445	5,645
Collateral-dependent Loans, Balance	394	446
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss, Ending Balance	$ 6,966	9,205	4,959	6,311
Number of Collateral-dependent Loans	1
Collateral-dependent Loans, Balance	$ 57
Residential Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss, Ending Balance	45	47	$ 206	$ 869
Financing Receivable, Troubled Debt Restructuring	$ 172	$ 181
Number of Collateral-dependent Loans	3	2
Collateral-dependent Loans, Balance	$ 420	$ 346
Other Consumer Loan [Member]
Financing Receivable, Principal and Interest Deferred Payments	84	2,500
Commercial Real Estate [Member]
Financing Receivable, Principal and Interest Deferred Payments		7,800
Commercial Loan [Member]
Financing Receivable, Principal and Interest Deferred Payments		33
Restructured Loans [Member]
Financing Receivable, Troubled Debt Restructuring	1,965	6,221
Impaired Loans, Restructured, Nonaccrual Status	0	3,420
Nonperforming Financial Instruments [Member]
Financing Receivable, Allowance for Credit Loss, Ending Balance	$ 0	$ 0

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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