Note 11 - Equity Incentive Plan - Total Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Stock-based compensation expense	$ 4,150	$ 4,081	$ 7,867	$ 6,626
Cost of Sales [Member]
Stock-based compensation expense	167	227	351	403
Research and Development Expense [Member]
Stock-based compensation expense	653	503	1,170	870
Selling, General and Administrative Expenses [Member]
Stock-based compensation expense	$ 3,330	$ 3,351	$ 6,346	$ 5,323