Note 4 - Loans - Age Analysis of Past Due Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loans, past due	$ 6,549	$ 4,916
Loans, current	1,045,696	1,027,987
Gross loans	1,052,245	1,032,903
Recorded investment greater than 90 days and accruing	2
Financial Asset, 30 to 59 Days Past Due [Member]
Loans, past due	3,173	1,397
Financial Asset, 60 to 89 Days Past Due [Member]
Loans, past due	152	373
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans, past due	3,224	3,146
Commercial Portfolio Segment [Member]
Loans, past due	710	71
Loans, current	138,160	141,126
Gross loans	138,870	141,197
Recorded investment greater than 90 days and accruing
Commercial Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Loans, past due	710	71
Commercial Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Loans, past due
Commercial Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member]
Gross loans	765,765	739,583
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans, past due
Loans, current	34,394	26,830
Gross loans	34,394	26,830
Recorded investment greater than 90 days and accruing
Commercial Real Estate Portfolio Segment [Member] | Commercial Non-owner Occupied [Member]
Loans, past due	1,097
Loans, current	512,955	493,920
Gross loans	514,052	493,920
Recorded investment greater than 90 days and accruing
Commercial Real Estate Portfolio Segment [Member] | Commercial Owner Occupied Loan [Member]
Loans, past due	3,757	3,758
Loans, current	213,562	215,075
Gross loans	217,319	218,833
Recorded investment greater than 90 days and accruing
Commercial Real Estate Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Construction Loans [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Non-owner Occupied [Member]
Loans, past due	1,097
Commercial Real Estate Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Owner Occupied Loan [Member]
Loans, past due	654	655
Commercial Real Estate Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Construction Loans [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Non-owner Occupied [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Owner Occupied Loan [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Construction Loans [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Non-owner Occupied [Member]
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Owner Occupied Loan [Member]
Loans, past due	3,103	3,103
Residential Portfolio Segment [Member]
Gross loans	117,689	118,799
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Loans, past due	689	737
Loans, current	31,309	32,302
Gross loans	31,998	33,039
Recorded investment greater than 90 days and accruing
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due
Loans, current	62,533	63,661
Gross loans	62,533	63,661
Recorded investment greater than 90 days and accruing
Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Loans, past due	90	100
Loans, current	23,068	21,999
Gross loans	23,158	22,099
Recorded investment greater than 90 days and accruing
Residential Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Loans, past due	513	371
Residential Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due
Residential Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member] | Home Equity Loan [Member]
Loans, past due	61	100
Residential Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Loans, past due	57	323
Residential Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due
Residential Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member] | Home Equity Loan [Member]
Loans, past due	29
Residential Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate Loan [Member] | Individual Tax Identification Number Loan [Member]
Loans, past due	119	43
Residential Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate Loan [Member] | Mortgage Receivable [Member]
Loans, past due
Residential Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Home Equity Loan [Member]
Loans, past due
Consumer Portfolio Segment [Member]
Loans, past due	206	250
Loans, current	29,715	33,074
Gross loans	29,921	33,324
Recorded investment greater than 90 days and accruing	2
Consumer Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Loans, past due	138	200
Consumer Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Loans, past due	66	50
Consumer Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans, past due	$ 2