Note 8 - Internal Risk Ratings and Payment Activity (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	$ 821,129	$ 820,419
Excluding Retail Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	672,155	671,109
Pass [Member] | Excluding Retail Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	650,380	648,527
Special Mention [Member] | Excluding Retail Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	6,602	6,660
Substandard [Member] | Excluding Retail Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	15,173	15,922
Doubtful [Member] | Excluding Retail Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	0	0
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	164,071	168,031
Commercial Portfolio Segment [Member] | Construction Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	47,634	56,209
Commercial Portfolio Segment [Member] | Secured by Commercial Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	351,550	336,050
Commercial Portfolio Segment [Member] | Secured by Residential Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	70,652	72,443
Commercial Portfolio Segment [Member] | Pass [Member] | Commercial and Industrial [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	154,860	158,247
Commercial Portfolio Segment [Member] | Pass [Member] | Construction Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	47,634	56,209
Commercial Portfolio Segment [Member] | Pass [Member] | Secured by Commercial Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	340,594	324,936
Commercial Portfolio Segment [Member] | Pass [Member] | Secured by Residential Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	69,044	70,759
Commercial Portfolio Segment [Member] | Special Mention [Member] | Commercial and Industrial [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	3,610	3,665
Commercial Portfolio Segment [Member] | Special Mention [Member] | Construction Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	0	0
Commercial Portfolio Segment [Member] | Special Mention [Member] | Secured by Commercial Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	2,992	2,995
Commercial Portfolio Segment [Member] | Special Mention [Member] | Secured by Residential Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	0	0
Commercial Portfolio Segment [Member] | Substandard [Member] | Commercial and Industrial [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	5,601	6,119
Commercial Portfolio Segment [Member] | Substandard [Member] | Construction Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	0	0
Commercial Portfolio Segment [Member] | Substandard [Member] | Secured by Commercial Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	7,964	8,119
Commercial Portfolio Segment [Member] | Substandard [Member] | Secured by Residential Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	1,608	1,684
Commercial Portfolio Segment [Member] | Doubtful [Member] | Commercial and Industrial [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	0	0
Commercial Portfolio Segment [Member] | Doubtful [Member] | Construction Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	0	0
Commercial Portfolio Segment [Member] | Doubtful [Member] | Secured by Commercial Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	0	0
Commercial Portfolio Segment [Member] | Doubtful [Member] | Secured by Residential Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	0	0
State and Political Subdivisions Portfolio Segment [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	38,248	38,376
State and Political Subdivisions Portfolio Segment [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	38,248	38,376
State and Political Subdivisions Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	0	0
State and Political Subdivisions Portfolio Segment [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	0	0
State and Political Subdivisions Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases receivable	$ 0	$ 0