Note 4 - Supplemental Balance Sheet - Composition of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Cost	$ 16,344	$ 15,990
Accumulated Amortization	9,259	8,796
Net	7,085	7,194
Trademarks [Member]
Cost	3,411	3,404
Accumulated Amortization	0
Net	3,411	3,404
Customer Relationships [Member]
Cost	6,618	6,395
Accumulated Amortization	4,208	3,975
Net	2,410	2,420
Patented Technology [Member]
Cost	5,545	5,455
Accumulated Amortization	4,595	4,417
Net	950	1,038
Distributor Relationships [Member]
Cost	377	377
Accumulated Amortization	377	368
Net		9
Trade Names [Member]
Cost	393	359
Accumulated Amortization	79	36
Net	$ 314	$ 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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