Note 11 - Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2019

Notes Tables

Share-based Payment Arrangement, Cost by Plan [Table Text Block]

	Three Months Ended September   30 ,				Nine Months Ended September   30 ,
	2019		2018		2019		2018
Stock options and employee stock purchase plan awards
Research and development	$	—	$	3	$	—	$	21
Selling, general and administrative		—		7		—		48
Restricted stock
Research and development		68		23		129		57
Selling, general and administrative		236		136		581		194
Stock appreciation rights
Research and development		132		—		114		—
Selling, general and administrative		132		112		114		198
Total stock-based compensation	$	568	$	281	$	938	$	518

Share-based Payment Arrangement, Option, Activity [Table Text Block]

	Number of Options
Options outstanding at December 31, 2018		2,313
Granted		—
Canceled or forfeited		(749	)
Exercised		—
Options outstanding at September 30, 2019		1,564
Weighted-average remaining contractual life (in years)		5.7

Schedule of Nonvested Share Activity [Table Text Block]

	Shares			Weighted -Average Grant Date Fair Value
Unvested RSAs at December 31, 2018		290,300		$	3.45
Granted		1,308,613		$	1.91
Vested		(254,500	)	$	3.45
Canceled or forfeited		(35,800	)	$	3.45
Unvested RSAs at September 30, 2019		1,308,613		$	1.91