Note 1 - Basis of Presentation and Significant Accounting Policies (Details Textual)				12 Months Ended
		Jan. 01, 2021 USD ($)		Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)		Dec. 31, 2020 USD ($)
Number of Operating Segments				1
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Total				$ 1,340,000
Minimum Principal Balance of Loans for Quarterly Rating Review				500,000
Restructured Loans, Reserves				$ 500,000
Off-Balance-Sheet, Credit Loss, Liability, Ending Balance	[1]	$ 66,000
Lessee, Operating Lease, Term of Contract (Year)				10 years
Number of Reportable Segments				1
Goodwill, Impairment Loss				$ 0
Financing Receivable, Allowance for Credit Loss, Ending Balance		26,182,000	[2]	30,556,000	$ 27,858,000	[3]	$ 26,182,000
Deferred Tax Assets, Net of Valuation Allowance, Total		17,493,000	[4]	21,874,000	19,213,000
Retained Earnings (Accumulated Deficit), Ending Balance		237,585,000	[5]	292,971,000	264,824,000	[3]
Other Assets, Total				$ 103,673,000	$ 106,691,000	[3]
Effective Income Tax Rate Reconciliation, Percent, Total				22.43%	23.09%		22.09%
Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Loss, Ending Balance		$ 5,880,000
Cumulative Effect, Period of Adoption, Adjustment [Member]
Effective Income Tax Rate Reconciliation, Percent, Total		23.37%
Accounting Standards Update 2016-13 [Member]
Other Assets, Total		$ 57,000
Accounting Standards Update 2016-13 [Member] | Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Loss, Ending Balance		57,000
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Off-Balance-Sheet, Credit Loss, Liability, Ending Balance	[1]	509,000
Financing Receivable, Allowance for Credit Loss, Ending Balance		13,107,000	[2]				$ 13,107,000
Deferred Tax Assets, Net of Valuation Allowance, Total	[4]	1,813,000
Retained Earnings (Accumulated Deficit), Ending Balance	[5]	$ (5,870,000)
Furniture and Fixtures [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)				5 years
Furniture and Fixtures [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)				10 years
Equipment, Computer Hardware and Software [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)				3 years
Equipment, Computer Hardware and Software [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)				5 years
Building and Building Improvements [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)				7 years
Building and Building Improvements [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)				40 years
Land and Land Improvements [Member]
Property, Plant and Equipment, Useful Life (Year)				20 years
Other Assets [Member]
Equity Securities without Readily Determinable Fair Value, Amount				$ 3,780,000	$ 3,850,000
Other Liabilities [Member]
Off-Balance-Sheet, Credit Loss, Liability, Ending Balance				1,200,000
Investment in Federal Home Loan Bank (FHLB) and Federal Reserve Bank (FRB) Stock [Member] | Other Assets [Member]
Investment Owned, at Cost				$ 10,020,000.00	$ 9,780,000

[1] Adjustment to the reserve for unfunded commitments related to the adoption of ASU 2016-13.

[2] Calculated adjustment to the ACL related to the adoption of ASU 2016-13. Includes additional reserve related to purchased deteriorated loans of $5.88 million.

[3] Derived from audited financial statements

[4] Effect of deferred tax assets related to the adjustment to the ACL form the adoption of ASU 2016-13 using a 23.37% tax rate.

[5] Net adjustment to retained earnings related to the adoption of ASU 2016-13.