Note 4 - Loans and Allowance for Loan Losses - Credit Quality Information (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loans	$ 974,650	$ 952,496
Pass [Member]
Loans	917,554	919,809
Special Mention [Member]
Loans	44,898	24,585
Substandard [Member]
Loans	11,517	7,383
Doubtful [Member]
Loans	681	719
Residential Portfolio Segment [Member] | Real Estate Sector [Member]
Loans	346,864	347,766
Residential Portfolio Segment [Member] | Real Estate Sector [Member] | Pass [Member]
Loans	342,785	343,851
Residential Portfolio Segment [Member] | Real Estate Sector [Member] | Special Mention [Member]
Loans	1,028	1,997
Residential Portfolio Segment [Member] | Real Estate Sector [Member] | Substandard [Member]
Loans	3,051	1,918
Residential Portfolio Segment [Member] | Real Estate Sector [Member] | Doubtful [Member]
Loans
Commercial Portfolio Segment [Member] | Real Estate Sector [Member]
Loans	354,374	351,360
Commercial Portfolio Segment [Member] | Real Estate Sector [Member] | Pass [Member]
Loans	312,089	335,436
Commercial Portfolio Segment [Member] | Real Estate Sector [Member] | Special Mention [Member]
Loans	36,496	12,260
Commercial Portfolio Segment [Member] | Real Estate Sector [Member] | Substandard [Member]
Loans	5,789	3,664
Commercial Portfolio Segment [Member] | Real Estate Sector [Member] | Doubtful [Member]
Loans
Commercial Portfolio Segment [Member] | Commercial and Industrial Sector [Member]
Loans	80,721	85,586
Commercial Portfolio Segment [Member] | Commercial and Industrial Sector [Member] | Pass [Member]
Loans	74,264	75,201
Commercial Portfolio Segment [Member] | Commercial and Industrial Sector [Member] | Special Mention [Member]
Loans	4,109	7,975
Commercial Portfolio Segment [Member] | Commercial and Industrial Sector [Member] | Substandard [Member]
Loans	1,667	1,691
Commercial Portfolio Segment [Member] | Commercial and Industrial Sector [Member] | Doubtful [Member]
Loans	681	719
Construction Portfolio Segment [Member] | Real Estate Sector [Member]
Loans	50,017	35,605
Construction Portfolio Segment [Member] | Real Estate Sector [Member] | Pass [Member]
Loans	45,985	33,342
Construction Portfolio Segment [Member] | Real Estate Sector [Member] | Special Mention [Member]
Loans	3,179	2,263
Construction Portfolio Segment [Member] | Real Estate Sector [Member] | Substandard [Member]
Loans	853
Construction Portfolio Segment [Member] | Real Estate Sector [Member] | Doubtful [Member]
Loans
Consumer Portfolio Segment [Member]
Loans	121,494	113,637
Consumer Portfolio Segment [Member] | Pass [Member]
Loans	121,337	113,527
Consumer Portfolio Segment [Member] | Special Mention [Member]
Loans
Consumer Portfolio Segment [Member] | Substandard [Member]
Loans	157	110
Consumer Portfolio Segment [Member] | Doubtful [Member]
Loans
Other Portfolio Segment [Member]
Loans	21,180	18,542
Other Portfolio Segment [Member] | Pass [Member]
Loans	21,094	18,452
Other Portfolio Segment [Member] | Special Mention [Member]
Loans	86	90
Other Portfolio Segment [Member] | Substandard [Member]
Loans
Other Portfolio Segment [Member] | Doubtful [Member]
Loans