Note 9 - Commitments and Contingencies - Supplemental Lease Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Right-of-use asset, net and lease liabilities (in thousands)	$ 3,950		$ 2,889
Weighted average remaining lease term (years) (Year)	4 years		3 years 182 days
Weighted average discount rate	4.30%		3.80%
Lease expense	$ 284	$ 160
Cost of Sales [Member]
Lease expense	218	78
General and Administrative Expense [Member]
Lease expense	56	52
Research and Development Expense [Member]
Lease expense	$ 10	$ 30