Note 8 - Leases (Details Textual) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating Lease, Weighted Average Remaining Lease Term (Year)	2 years 8 months 12 days	2 years 9 months 18 days
Operating Lease, Weighted Average Discount Rate, Percent	6.28%	6.25%
Operating Expenses and Cost of Revenues [Member]
Operating Lease, Expense	$ 0.3	$ 0.3