Note 5 - Loans - Age Analysis of Past Due Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Loans, past due	$ 4,559	$ 11,247
Loans, current	799,652	705,392
Gross loans	804,211	716,639
Recorded investment greater than 90 days and accruing		88
Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	999	1,369
Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	186	699
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	3,374	9,179
Commercial Portfolio Segment [Member]
Loans, past due	51	664
Loans, current	153,793	132,141
Gross loans	153,844	132,805
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		30
Commercial Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due		634
Commercial Real Estate Portfolio Segment [Member]
Gross loans	496,742	427,992
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans, past due
Loans, current	57,771	28,319
Gross loans	57,771	28,319
Recorded investment greater than 90 days and accruing
Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Loans, past due	1,196	5,729
Loans, current	286,259	237,645
Gross loans	287,455	243,374
Recorded investment greater than 90 days and accruing
Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Loans, past due	114	1,071
Loans, current	151,402	155,228
Gross loans	151,516	156,299
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		64
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Owner Occupied Loan [Member]
Loans, past due
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	5,665
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	1,071
Residential Portfolio Segment [Member]
Gross loans	101,944	105,969
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Loans, past due	1,796	1,986
Loans, current	43,770	47,120
Gross loans	45,566	49,106
Recorded investment greater than 90 days and accruing
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due	1,003	1,275
Loans, current	11,863	12,365
Gross loans	12,866	13,640
Recorded investment greater than 90 days and accruing
Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Loans, past due	152	234
Loans, current	43,360	42,989
Gross loans	43,512	43,223
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	567	1,018
Residential Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due	147
Residential Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Home Equity Loan [Member]
Loans, past due	68	137
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	80	118
Residential Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due		404
Residential Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Home Equity Loan [Member]
Loans, past due	36	97
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	1,149	850
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	856	871
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	247	288
Loans, current	51,434	49,585
Gross loans	51,681	49,873
Recorded investment greater than 90 days and accruing		88
Consumer Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	166	150
Consumer Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	70	50
Consumer Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	$ 11	$ 88