Note 8 - Loans and Related Allowance for Loan and Lease Losses - Classes of the Loan Portfolio Summarized by Credit Quality (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Loans	$ 999,282	$ 992,109
Commercial And Industrial [Member]
Loans	85,861	83,857
Real Estate Construction Porfolio Segment [Member]
Loans	57,564	56,731
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans	347,739	336,487
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans	492,914	498,247
Consumer Portfolio Segment [Member]
Loans	15,204	16,787
Pass [Member]
Loans	967,659	965,166
Pass [Member] \| Commercial And Industrial [Member]
Loans	78,163	77,002
Pass [Member] \| Real Estate Construction Porfolio Segment [Member]
Loans	57,564	55,397
Pass [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans	342,571	332,475
Pass [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans	474,166	483,516
Pass [Member] \| Consumer Portfolio Segment [Member]
Loans	15,195	16,776
Special Mention [Member]
Loans	12,617	13,076
Special Mention [Member] \| Commercial And Industrial [Member]
Loans	4,585	4,572
Special Mention [Member] \| Real Estate Construction Porfolio Segment [Member]
Loans		1,334
Special Mention [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans	989	553
Special Mention [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans	7,043	6,617
Substandard [Member]
Loans	19,006	13,867
Substandard [Member] \| Commercial And Industrial [Member]
Loans	3,113	2,283
Substandard [Member] \| Real Estate Construction Porfolio Segment [Member]
Loans
Substandard [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans	4,179	3,459
Substandard [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans	11,705	8,114
Substandard [Member] \| Consumer Portfolio Segment [Member]
Loans	9	11
Doubtful [Member]
Loans
Doubtful [Member] \| Commercial And Industrial [Member]
Loans
Doubtful [Member] \| Real Estate Construction Porfolio Segment [Member]
Loans
Doubtful [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans
Doubtful [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans