Note 8 - Stock-based Compensation - Assumptions (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Risk-free interest rate		0.84%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Expected term (Year)		5 years		5 years
Expected volatility		46.80%
Minimum [Member]
Risk-free interest rate	2.85%		1.91%	0.46%
Expected term (Year)	3 years 3 months		3 years 3 months
Expected volatility	45.90%		45.80%	47.10%
Maximum [Member]
Risk-free interest rate	2.90%		2.90%	0.92%
Expected term (Year)	6 years		6 years
Expected volatility	48.10%		48.50%	92.60%