Note 5 - Loans - Performing and Nonperforming Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Gross loans	$ 946,251	$ 879,835	$ 804,211
Commercial Portfolio Segment [Member]
Gross loans	135,543	142,405	146,881
Commercial Real Estate Portfolio Segment [Member]
Gross loans	660,893	585,593	503,705
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	22,563	15,902
Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	433,708	377,668
Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	204,622	192,023
Residential Portfolio Segment [Member]
Gross loans	98,770	101,912	101,944
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	37,446	41,188
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	34,366	30,377
Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	26,958	30,347
Consumer Portfolio Segment [Member]
Gross loans	51,045	49,925	$ 51,681
Performing Financial Instruments [Member]
Gross loans	942,105	874,036
Performing Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Gross loans	134,584	140,802
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	22,563	15,902
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	433,160	377,668
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	204,622	191,423
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	35,058	38,279
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	34,181	29,771
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	26,915	30,302
Performing Financial Instruments [Member] | Consumer Portfolio Segment [Member]
Gross loans	51,022	49,889
Nonperforming Financial Instruments [Member]
Gross loans	4,146	5,799
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Gross loans	959	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	548
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	2,388	2,909
Nonperforming Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	185	606
Nonperforming Financial Instruments [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	43	45
Nonperforming Financial Instruments [Member] | Consumer Portfolio Segment [Member]
Gross loans	$ 23	$ 36