Note 15 - Equity-based Compensation - Weighted-average Assumptions Used in Determining the Value of Options Granted to Employees and Directors (Details) - Employees and Directors [Member] - $ / shares	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Expected price volatility	158.04%	163.95%
Expected term (Year)	6 years 5 months 12 days	6 years 2 months 8 days
Risk-free interest rate	2.29%	0.92%
Dividend yield	0.00%	0.00%
Weighted-average fair value of options granted during the period (in dollars per share)	$ 0.27	$ 0.71