Note 6 - Stockholders' Equity and Stock-based Compensation - Stock-based Compensation Expense by Recorded Location (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Total stock-based compensation expense	$ 7,181	$ 5,191
Cost of Sales [Member]
Total stock-based compensation expense	0	217
Research and Development Expense [Member]
Total stock-based compensation expense	3,491	1,563
Selling and Marketing Expense [Member]
Total stock-based compensation expense	0	733
General and Administrative Expense [Member]
Total stock-based compensation expense	$ 3,690	$ 2,678