Note 11 - Net Loss Per Share - Calculation of Basic and Diluted Net (Loss) Income Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Net loss	$ (29,430)	$ (16,116)	$ (54,531)	$ (32,123)
Shares used to compute net loss per share - basic and diluted (in shares)	126,428,298	120,925,570	126,111,777	118,174,099
Net loss per share - basic and diluted (in dollars per share)	$ (0.23)	$ (0.13)	$ (0.43)	$ (0.27)