Note 1 - Basis of Presentation - Impact of Topic 606 (Details) - USD ($) $ in Thousands	3 Months Ended					6 Months Ended		12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Total net revenue	$ 4,573			$ 3,083		$ 8,631	$ 4,782
Total cost of revenue	2,042			1,336		3,785	2,229
Net Income	1,058			160		1,951	(348)
Service [Member]
Total net revenue	4,508			2,993		8,471	4,692
Total cost of revenue	2,042			1,249		3,649	2,142
Product [Member]
Total net revenue	65			90		160	90
Total cost of revenue				87		$ 136	$ 87
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Total net revenue
Total cost of revenue
Net Income
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Service [Member]
Total net revenue		166	162	159	149			636
Total cost of revenue		62	51	50	46			209
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Product [Member]
Total net revenue		(166)	(162)	(159)	(149)			(636)
Total cost of revenue		$ (62)	$ (51)	$ (50)	$ (46)			$ (209)