Note 10 - Net Loss Per Share (Tables)

9 Months Ended

Sep. 30, 2021

Notes Tables

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

	Three Months Ended						Nine Months Ended
	September 30,						September 30,
	2021			2020			2021			2020
Weighted average common shares outstanding:
Basic		119,374			117,564			118,677			117,450
Dilutive unvested stock, convertible preferred stock, Common Stock Warrants and IPO Warrants		—			—			—			—
Diluted		119,374			117,564			118,677			117,450
Basic and diluted net loss per share attributable to common stockholders	$	(0.03	)	$	(0.09	)	$	(0.23	)	$	(0.19	)

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

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2021		2020		2021		2020
Unvested stock (1)		1,831		848		1,581		993
Convertible preferred stock		34,095		16,869		29,174		16,386
Common Stock Warrants		2,510		1,979		2,486		1,972
IPO Warrants(2)		12,082		12,082		12,082		12,082
Total potentially dilutive common shares		50,518		31,778		45,323		31,433