Note 8 - Leases - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Operating lease cost	$ 294	$ 389	$ 618	$ 781
Short-term lease cost	$ 32	$ 10	$ 40	$ 22
Weighted average remaining lease term (in years) (Year)	6 years 3 months 18 days		6 years 3 months 18 days
Weighted average discount rate	4.30%		4.30%
Minimum [Member]
Range of remaining lease terms (in years) (Year)			9 months 18 days
Maximum [Member]
Range of remaining lease terms (in years) (Year)			9 years 9 months 18 days