Note 14 - Stockholders' Equity - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Stock-based compensation expense	$ 2,255	$ 2,201
Cost of Sales [Member]
Stock-based compensation expense	104	73
Research and Development Expense [Member]
Stock-based compensation expense	36	77
General and Administrative Expense [Member]
Stock-based compensation expense	$ 2,115	$ 2,051