Note 12 - Net Loss Per Share of Common Stock (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	Year Ended
	December 31,
	2021			2020
Net loss	$	(39,151	)	$	(30,543	)
Basic and diluted net loss per share	$	(1.95	)	$	(1.93	)
Weighted-average shares used to compute basic and diluted net loss per share		20,070			15,790

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	Year Ended
	December 31,
	2021		2020
Options to purchase common stock		2,439,253		2,173,776
Restricted stock units		—		233