Note 4 - Loans and Allowance for Loan Losses - Composition of Loan Portfolio (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Total loans (Note 4)	$ 534,146	$ 518,716
Commercial Portfolio Segment [Member]
Total loans (Note 4)	$ 123,403	$ 99,864
Total loans, percentage	23.10%	19.30%
Commercial Real Estate Portfolio Segment [Member]
Total loans (Note 4)	$ 303,404	$ 302,084
Total loans, percentage	56.80%	58.20%
Residential Portfolio Segment [Member]
Total loans (Note 4)	$ 79,808	$ 87,172
Total loans, percentage	14.90%	16.80%
Consumer Portfolio Segment [Member]
Total loans (Note 4)	$ 303,404	$ 302,084
Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Total loans (Note 4)	$ 23,749	$ 25,856
Total loans, percentage	4.50%	5.00%
Consumer Portfolio Segment [Member] | Other Loan [Member]
Total loans (Note 4)	$ 3,782	$ 3,740
Total loans, percentage	0.70%	0.70%