Note 4 - Loans - Internal Risk Rating by Loan Class (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Gross loans	$ 927,480	$ 879,835
Commercial Portfolio Segment [Member]
Gross loans	132,091	142,405
Commercial Real Estate Portfolio Segment [Member]
Gross loans	647,350	585,593
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	20,496	15,902
Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	431,246	377,668
Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	195,608	192,023
Residential Portfolio Segment [Member]
Gross loans	100,539	101,912
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	38,353	41,188
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	33,473	30,377
Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	28,713	30,347
Consumer Portfolio Segment [Member]
Gross loans	47,500	49,925
Pass [Member]
Gross loans	864,239	809,332
Pass [Member] | Commercial Portfolio Segment [Member]
Gross loans	113,743	117,087
Pass [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	20,471	14,762
Pass [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	414,540	364,230
Pass [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	175,909	171,005
Pass [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	32,497	34,923
Pass [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	32,524	28,981
Pass [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	27,086	28,457
Pass [Member] | Consumer Portfolio Segment [Member]
Gross loans	47,469	49,887
Watch [Member]
Gross loans	42,114	48,863
Watch [Member] | Commercial Portfolio Segment [Member]
Gross loans	16,508	22,213
Watch [Member] | Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	25
Watch [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Gross loans	10,908	9,160
Watch [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	12,590	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	770	791
Watch [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	1,313	1,501
Watch [Member] | Consumer Portfolio Segment [Member]
Gross loans
Special Mention [Member]
Gross loans	2,603	8,052
Special Mention [Member] | Commercial Portfolio Segment [Member]
Gross loans	31	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	382	2,900
Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	2,190	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	18,524	13,588
Substandard [Member] | Commercial Portfolio Segment [Member]
Gross loans	1,809	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	5,416	1,378
Substandard [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Gross loans	4,919	1,913
Substandard [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Gross loans	5,856	6,265
Substandard [Member] | Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Gross loans	179	605
Substandard [Member] | Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Gross loans	314	326
Substandard [Member] | Consumer Portfolio Segment [Member]
Gross loans	31	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