Note 13 - Stock-based Compensation Plan - Allocation of Share-based Compensation Expense (Details) - Restricted Stock [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share-Based Payment Arrangement, Expense	$ 551	$ 454	$ 923	$ 723
Cost of Sales [Member]
Share-Based Payment Arrangement, Expense	15	7	26	7
Selling and Marketing Expense [Member]
Share-Based Payment Arrangement, Expense	7	6	14	9
Research and Development Expense [Member]
Share-Based Payment Arrangement, Expense	18	16	37	26
General and Administrative Expense [Member]
Share-Based Payment Arrangement, Expense	$ 511	$ 425	$ 846	$ 681