Note 2 - Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2019

Notes Tables

Cumulative Effect of Adjustments for New Accounting Pronouncements on Balance Sheet [Table Text Block]

			Adjustments
			Due to
	December 31,		Adoption of			January 1,
	2018		ASC 842			2019
Other assets	$	171	$	629	(1)	$	800
Total assets	$	46,834	$	629	(1)	$	47,463
Accrued liabilities	$	6,766	$	230	(2)	$	6,996
Total current liabilities	$	10,760	$	230	(2)	$	10,990
Other noncurrent liabilities	$	634	$	399	(2)	$	1,033
Total liabilities	$	41,922	$	629	(2)	$	42,551
Total liabilities and stockholders' equity	$	46,834	$	629	(2)	$	47,463

Contract with Customer, Asset and Liability [Table Text Block]

	June 30,		December 31,		Six Months
	2019		2018		Change
Customer contracts liabilities:
Marketing programs	$	552	$	639	$	(87	)
Other		-		47		(47	)
Total	$	552	$	686	$	(134	)

Revenue from External Customers by Geographic Areas [Table Text Block]

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2019		2018		2019		2018
North America	$	663	$	4,552	$	2,455	$	7,158
Asia Pacific		343		630		1,310		1,521
Europe and Middle East		43		329		289		531
Latin America		3		14		10		14
Total	$	1,052	$	5,525	$	4,064	$	9,224

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

	Six Months Ended
	June 30,
	2019		2018
Stock options to purchase common stock		5,314,375		4,209,355
Warrants to purchase common stock		642,622		642,622
Restricted common stock awards		393,051		66,250