Note 8 - Loans and Related Allowance for Loan and Lease Losses - Nonaccrual Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loans, current balance	$ 8,405	$ 8,879
Loans, past due	0
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member]
Loans, current balance	1,175	1,162
Loans, past due
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member]
Loans, current balance	3,287	3,289
Loans, past due
Residential Portfolio Segment [Member]
Loans, current balance	2,180	2,576
Loans, past due
Commercial And Industrial [Member]
Loans, current balance	835	946
Loans, past due	0
Home Equity Lines of Credit [Member]
Loans, current balance	699	709
Loans, past due
Consumer Portfolio Segment [Member]
Loans, current balance	229	197
Loans, past due	$ 0