Note 11 - Net Loss Per Share - Summary of Antidilutive Securities (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Potentially dilutive securities excluded from denominator of the diluted earnings per share computation (in shares)	22,346,418	15,623,804	20,466,549	13,753,853
Share-Based Payment Arrangement, Option [Member]
Potentially dilutive securities excluded from denominator of the diluted earnings per share computation (in shares)	18,151,747	14,735,710	17,019,217	13,170,959
Restricted Stock Units (RSUs) [Member]
Potentially dilutive securities excluded from denominator of the diluted earnings per share computation (in shares)	3,629,741	660,660	2,840,178	353,738
Warrant [Member] | Common Stock [Member]
Potentially dilutive securities excluded from denominator of the diluted earnings per share computation (in shares)	227,434	227,434	227,434	229,156
Employee Stock Purchase Plan [Member]
Potentially dilutive securities excluded from denominator of the diluted earnings per share computation (in shares)	337,496	0	379,720	0