Note 4 - Loans - Performing and Nonperforming Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Gross loans	$ 824,874	$ 804,211
Commercial Portfolio Segment [Member]
Gross loans	147,212	153,844
Commercial Real Estate Portfolio Segment [Member]
Gross loans	531,890	496,742
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	14,700	36,792
Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	333,766	292,615
Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	183,424	167,335
Residential Portfolio Segment [Member]
Gross loans	94,340	101,944
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	42,063	45,566
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	21,119	20,425
Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	31,158	35,953
Consumer Portfolio Segment [Member]
Gross loans	51,432	51,681
Performing Financial Instruments [Member]
Gross loans	817,269	792,825
Performing Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Gross loans	144,903	151,095
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	14,700	36,792
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	333,766	291,419
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	182,807	166,551
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	38,862	41,990
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	20,493	18,511
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	30,343	35,036
Performing Financial Instruments [Member] | Consumer Portfolio Segment [Member]
Gross loans	51,395	51,431
Nonperforming Financial Instruments [Member]
Gross loans	7,605	11,386
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Gross loans	2,309	2,749
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		1,196
Nonperforming Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	617	784
Nonperforming Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	3,201	3,576
Nonperforming Financial Instruments [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	626	1,914
Nonperforming Financial Instruments [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	815	917
Nonperforming Financial Instruments [Member] | Consumer Portfolio Segment [Member]
Gross loans	$ 37	$ 250