Note 4 - Supplemental Balance Sheet - Composition of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Cost	$ 15,990	$ 12,234
Accumulated Amortization	8,796	8,288
Net	7,194	3,946
Trademarks [Member]
Cost	3,404	3,411
Accumulated Amortization	0
Net	3,404	3,411
Customer Relationships [Member]
Cost	6,395	3,971
Accumulated Amortization	3,975	3,716
Net	2,420	255
Patented Technology [Member]
Cost	5,455	4,482
Accumulated Amortization	4,417	4,217
Net	1,038	265
Distributor Relationships [Member]
Cost	377	370
Accumulated Amortization	368	355
Net	9	$ 15
Trade Names [Member]
Cost	359
Accumulated Amortization	36
Net	$ 323

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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