Note 8 - Leases - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating lease cost	$ 247	$ 393	$ 865	$ 1,174
Short-term lease cost	$ 20	$ 13	$ 60	$ 35
Weighted average remaining lease term (in years) (Year)	6 years		6 years
Weighted average discount rate	4.20%		4.20%
Minimum [Member]
Range of remaining lease terms (in years) (Year)			6 months
Maximum [Member]
Range of remaining lease terms (in years) (Year)			9 years 7 months 6 days