Note 15 - Stock-based Compensation - Compensation Related to Stock-based Awards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Total stock-based compensation expense	$ 9,168	$ 9,830	$ 9,359
Tax effect on stock-based compensation expense	872	858	736
Net effect of stock-based compensation expense	8,296	8,972	8,623
Cost of Sales [Member]
Total stock-based compensation expense	4,656	4,435	3,633
Selling and Marketing Expense [Member]
Total stock-based compensation expense	766	1,081	916
General and Administrative Expense [Member]
Total stock-based compensation expense	$ 3,746	$ 4,314	$ 4,810