Note 4 - Loans - Internal Risk Rating by Loan Class (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Gross loans	$ 936,816	$ 879,835
Commercial Portfolio Segment [Member]
Gross loans	139,670	142,405
Commercial Real Estate Portfolio Segment [Member]
Gross loans	647,792	585,593
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	21,292	15,902
Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	427,088	377,668
Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	199,412	192,023
Residential Portfolio Segment [Member]
Gross loans	101,694	101,912
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	39,424	41,188
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	33,391	30,377
Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	28,879	30,347
Consumer Portfolio Segment [Member]
Gross loans	47,660	49,925
Pass [Member]
Gross loans	869,905	809,332
Pass [Member] | Commercial Portfolio Segment [Member]
Gross loans	111,385	117,087
Pass [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	21,266	14,762
Pass [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	415,385	364,230
Pass [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	181,084	171,005
Pass [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	33,483	34,923
Pass [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	32,430	28,981
Pass [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	27,247	28,457
Pass [Member] | Consumer Portfolio Segment [Member]
Gross loans	47,625	49,887
Watch [Member]
Gross loans	44,379	48,863
Watch [Member] | Commercial Portfolio Segment [Member]
Gross loans	25,629	22,213
Watch [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	26
Watch [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	5,398	9,160
Watch [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	11,235	15,198
Watch [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans
Watch [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	777	791
Watch [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	1,314	1,501
Watch [Member] | Consumer Portfolio Segment [Member]
Gross loans
Special Mention [Member]
Gross loans	2,554	8,052
Special Mention [Member] | Commercial Portfolio Segment [Member]
Gross loans	34	40
Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans		1,140
Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	385	2,900
Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	2,135	3,907
Special Mention [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans
Special Mention [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans
Special Mention [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans		63
Special Mention [Member] | Consumer Portfolio Segment [Member]
Gross loans		2
Substandard [Member]
Gross loans	19,978	13,588
Substandard [Member] | Commercial Portfolio Segment [Member]
Gross loans	2,622	3,065
Substandard [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans
Substandard [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	5,920	1,378
Substandard [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	4,958	1,913
Substandard [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	5,941	6,265
Substandard [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	184	605
Substandard [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	318	326
Substandard [Member] | Consumer Portfolio Segment [Member]
Gross loans	35	36
Doubtful [Member]
Gross loans
Doubtful [Member] | Commercial Portfolio Segment [Member]
Gross loans
Doubtful [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans
Doubtful [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans
Doubtful [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans
Doubtful [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans
Doubtful [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans
Doubtful [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans
Doubtful [Member] | Consumer Portfolio Segment [Member]
Gross loans