Note 13 - Basic and Diluted Net Loss Per Share - Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share (in shares)	16,464,509	9,994,096
Share-Based Payment Arrangement, Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share (in shares)	7,404,858	5,089,464
Warrant [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share (in shares)	1,021,076	1,013,383
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share (in shares)	8,038,575	3,891,249