Note 4 - Loans - Performing and Nonperforming Loans (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
Performing Financial Instruments [Member]
Gross loans	932,584	874,036
Performing Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Gross loans	138,312	140,802
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	21,292	15,902
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	427,088	377,668
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	199,412	191,423
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	36,811	38,279
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	33,207	29,771
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	28,835	30,302
Performing Financial Instruments [Member] | Consumer Portfolio Segment [Member]
Gross loans	47,627	49,889
Nonperforming Financial Instruments [Member]
Gross loans	4,232	5,799
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Gross loans	1,358	1,603
Nonperforming Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans
Nonperforming Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans
Nonperforming Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans		600
Nonperforming Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	2,613	2,909
Nonperforming Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	184	606
Nonperforming Financial Instruments [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	44	45
Nonperforming Financial Instruments [Member] | Consumer Portfolio Segment [Member]
Gross loans	$ 33	$ 36