Note 3 - Net Loss Per Share - Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Net loss	$ (9,623)	$ (8,636)
Net loss allocated to stockholders of the Company	$ (9,657)	$ (8,619)
Weighted-average shares of common stock outstanding used in computing net loss per share, basic (in shares)	5,218	4,265
Weighted-average shares of common stock outstanding used in computing net loss per share, diluted (in shares)	5,218	4,265
Basic (in dollars per share)	$ (1.85)	$ (2.02)
Diluted (in dollars per share)	$ (1.85)	$ (2.02)