Note 4 - Loans and the Allowance for Loan Losses - Credit Risk Profile by Internally Assigned Grade (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loans	$ 623,743	$ 619,718
Consumer Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans	96,954	94,687
Consumer Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans	449	186
Consumer Portfolio Segment [Member] | Automobile Loan [Member]
Loans	92,862	90,310
Consumer Portfolio Segment [Member] | Automobile Loan [Member] | Performing Financial Instruments [Member]
Loans	92,448	90,128
Consumer Portfolio Segment [Member] | Automobile Loan [Member] | Nonperforming Financial Instruments [Member]
Loans	414	182
Consumer Portfolio Segment [Member] | Other Loans [Member]
Loans	4,541	4,563
Consumer Portfolio Segment [Member] | Other Loans [Member] | Performing Financial Instruments [Member]
Loans	4,506	4,559
Consumer Portfolio Segment [Member] | Other Loans [Member] | Nonperforming Financial Instruments [Member]
Loans	35	4
Consumer Portfolio Segment [Member] | Residential Portfolio Segment [Member]
Loans	$ 97,403
Consumer Portfolio Segment [Member] | Commercial Portfolio Segment [Member]
Loans		$ 94,873