Note 6 - Goodwill, Intangible Assets and Long Term Assets - Composition of Intangible Assets (Details) - USD ($)	Jun. 26, 2016	Dec. 31, 2015
Trademarks [Member]
Cost	$ 3,413,000	$ 3,411,000
Accumulated Amortization	0	0
Net	3,413,000	3,411,000
Patents and Technology [Member]
Cost	5,561,000	4,482,000
Accumulated Amortization	4,327,000	4,217,000
Net	1,234,000	265,000
Customer Relationships [Member]
Cost	7,039,000	3,971,000
Accumulated Amortization	3,878,000	3,716,000
Net	3,161,000	255,000
Distributor Relationships [Member]
Cost	377,000	370,000
Accumulated Amortization	363,000	355,000
Net	14,000	15,000
Trade Names [Member]
Cost	399,000
Accumulated Amortization	20,000
Net	379,000
Cost	16,789,000	12,234,000
Accumulated Amortization	8,588,000	8,288,000
Net	$ 8,201,000	$ 3,946,000

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

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

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