Note 8 - Leases - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating lease cost	$ 324	$ 392
Short-term lease cost	$ 8	$ 12
Weighted average remaining lease term (in years) (Year)	6 years 146 days
Weighted average discount rate	4.30%
Minimum [Member]
Range of remaining lease terms (in years) (Year)	36 days
Maximum [Member]
Range of remaining lease terms (in years) (Year)	10 years