Note 4 - Loans and Allowance for Loan Losses - Risk Category of Commercial Loans by Class of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Loans receivable	$ 776,126	$ 777,052
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	221,514	216,360
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Owner Occupied [Member]
Loans receivable	59,815	61,694
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Nonowner Occupied [Member]
Loans receivable	129,535	117,188
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans receivable	32,164	37,478
Commercial and Industrial Portfolio Segment [Member]
Loans receivable	102,296	113,243
Commercial Portfolio Segment [Member]
Loans receivable	323,810	329,603
Pass [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Owner Occupied [Member]
Loans receivable	49,522	50,474
Pass [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Nonowner Occupied [Member]
Loans receivable	121,028	115,170
Pass [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans receivable	32,164	37,321
Pass [Member] | Commercial and Industrial Portfolio Segment [Member]
Loans receivable	85,857	92,417
Pass [Member] | Commercial Portfolio Segment [Member]
Loans receivable	288,571	295,382
Criticized [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Owner Occupied [Member]
Loans receivable	7,207	7,724
Criticized [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Nonowner Occupied [Member]
Loans receivable
Criticized [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans receivable
Criticized [Member] | Commercial and Industrial Portfolio Segment [Member]
Loans receivable	2,669	6,536
Criticized [Member] | Commercial Portfolio Segment [Member]
Loans receivable	9,876	14,260
Classified [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Owner Occupied [Member]
Loans receivable	3,086	3,496
Classified [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Nonowner Occupied [Member]
Loans receivable	8,507	2,018
Classified [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans receivable		157
Classified [Member] | Commercial and Industrial Portfolio Segment [Member]
Loans receivable	13,770	14,290
Classified [Member] | Commercial Portfolio Segment [Member]
Loans receivable	$ 25,363	$ 19,961