Note 5 - Loans - Age Analysis of Past Due Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Loans, past due	$ 3,432	$ 4,559
Loans, current	811,956	799,652
Gross loans	815,388	804,211
Recorded investment greater than 90 days and accruing
Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	1,067	999
Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	224	186
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	2,141	3,374
Commercial Portfolio Segment [Member]
Loans, past due		51
Loans, current	152,204	153,793
Gross loans	152,204	153,844
Recorded investment greater than 90 days and accruing
Commercial Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due		51
Commercial Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due
Commercial Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member]
Gross loans	518,138	496,742
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans, past due
Loans, current	22,275	36,792
Gross loans	22,275	36,792
Recorded investment greater than 90 days and accruing
Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Loans, past due	1,196	1,196
Loans, current	309,799	291,419
Gross loans	310,995	292,615
Recorded investment greater than 90 days and accruing
Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Loans, past due	145	114
Loans, current	184,723	167,221
Gross loans	184,868	167,335
Recorded investment greater than 90 days and accruing
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Construction Loans [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Non-owner Occupied [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Owner Occupied Loan [Member]
Loans, past due	145
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Construction Loans [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Non-owner Occupied [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Owner Occupied Loan [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Construction Loans [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Non-owner Occupied [Member]
Loans, past due	1,196	1,196
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Owner Occupied Loan [Member]
Loans, past due		114
Residential Portfolio Segment [Member]
Gross loans	94,266	101,944
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Loans, past due	1,393	1,796
Loans, current	41,836	43,770
Gross loans	43,229	45,566
Recorded investment greater than 90 days and accruing
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due	317	1,003
Loans, current	18,587	19,422
Gross loans	18,904	20,425
Recorded investment greater than 90 days and accruing
Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Loans, past due	220	152
Loans, current	31,913	35,801
Gross loans	32,133	35,953
Recorded investment greater than 90 days and accruing
Residential Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Loans, past due	489	567
Residential Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due	132	147
Residential Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Home Equity Loan [Member]
Loans, past due	165	68
Residential Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Loans, past due	144	80
Residential Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due
Residential Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Home Equity Loan [Member]
Loans, past due	55	36
Residential Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Loans, past due	760	1,149
Residential Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due	185	856
Residential Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Home Equity Loan [Member]
Loans, past due		48
Consumer Portfolio Segment [Member]
Loans, past due	161	247
Loans, current	50,619	51,434
Gross loans	50,780	51,681
Recorded investment greater than 90 days and accruing
Consumer Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	136	166
Consumer Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	25	70
Consumer Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due		$ 11