Note 2 - Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 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]

	March 31,		December 31,		Three Months
	2019		2018		Change
Customer contracts liabilities:
Marketing programs	$	627	$	639	$	(12	)
Other		52		47		5
Total	$	679	$	686	$	(7	)

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

	Three Months Ended
	March 31,
	2019		2018
North America	$	1,792	$	2,606
Asia Pacific		967		891
Europe and Middle East		246		202
Latin America		7		-
Total	$	3,012	$	3,699

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

	Three Months Ended
	March 31,
	2019		2018
Stock options to purchase common stock		5,593,130		3,690,902
Warrants to purchase common stock		642,622		642,622
Restricted common stock awards		419,147		22,500