Note 9 - Commitments and Contingencies - Supplemental Lease Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Right-of-use asset, net and lease liabilities (in thousands)	$ 4,273		$ 3,955
Weighted average remaining lease term (years) (Year)	3 years 8 months 12 days		3 years 6 months
Weighted average discount rate	4.30%		4.10%
Lease expense	$ 317	$ 284
Cost of Sales [Member]
Lease expense	219	218
General and Administrative Expense [Member]
Lease expense	53	56
Research and Development Expense [Member]
Lease expense	$ 45	$ 10