Note 6 - Leases - Lease Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Right-of-use assets	$ 4,645		$ 4,878
Weighted average remaining lease term (years) (Year)	7 years 2 months 1 day		7 years 3 months 29 days
Weighted average discount rate	3.04%		3.03%
Operating lease cost	$ 269	$ 249
Short-term lease cost	1	1
Total lease cost	270	250
Cash paid for amounts included in the measurement of lease liabilities	251	$ 243
Other Liabilities [Member]
Lease liabilities	$ 4,725		$ 4,940