Note 12 - Summary of Stock Options - Stock-based Compensation Expense Included in the Statement of Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Stock-based compensation expense	$ 868	$ 1,088	$ 2,737	$ 2,765
Cost of Sales [Member]
Stock-based compensation expense	64	76	193	191
Research and Development Expense [Member]
Stock-based compensation expense	118	131	361	330
Selling, General and Administrative Expenses [Member]
Stock-based compensation expense	$ 686	$ 881	$ 2,183	$ 2,244