Note 3 - Supplemental Balance Sheet Information - Composition of Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Cost	$ 12,496	$ 12,505
Accumulated Amortization	8,158	7,859
Net	4,338us-gaap_FiniteLivedIntangibleAssetsNet	4,646us-gaap_FiniteLivedIntangibleAssetsNet
Trademarks
Cost	3,567	3,567
Accumulated Amortization	0	0
Net	3,567	3,567
Patents and Technology
Cost	4,509	4,511
Accumulated Amortization	4,114	3,941
Net	395	570
Customer Relationships
Cost	4,029	4,033
Accumulated Amortization	3,679	3,562
Net	350	471
Distributor Relationships
Cost	391	393
Accumulated Amortization	365	356
Net	$ 26	$ 37

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=26713463&loc=d3e16323-109275

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