Note 15 - Stock-based Compensation - Stock-based Compensation (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Stock based compensation	$ 1,528,000	$ 862,000
Cost of Sales [Member]
Stock based compensation	29,000	15,000
General and Administrative Expense [Member]
Stock based compensation	842,000	550,000
Selling and Marketing Expense [Member]
Stock based compensation	336,000	163,000
Research and Development Expense [Member]
Stock based compensation	$ 321,000	$ 134,000