Note 5 - Geographic Information and Major Customer and Product Data - Summary of Revenues within Geographical Areas (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
UNITED STATES
Revenues	$ 24,976	$ 17,716	$ 66,821	$ 48,894
EMEA [Member]
Revenues	12,650	10,984	35,004	28,217
Rest of World [Member]
Revenues	3,311	2,537	8,222	6,262
Revenues	$ 40,937	$ 31,237	$ 110,047	$ 83,373

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Name:	us-gaap_Revenues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration