Note 6 - Goodwill, Intangible Assets and Long Term Assets (Detail) - USD ($) $ in Thousands	Mar. 27, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Cost	$ 16,933	$ 12,234
Accumulated Amortization	(8,458)	(8,288)
Net	8,475	3,946
Trademarks
Finite-Lived Intangible Assets [Line Items]
Cost	3,413	3,411
Accumulated Amortization	0	0
Net	3,413	3,411
Patents and Technology
Finite-Lived Intangible Assets [Line Items]
Cost	5,595	4,482
Accumulated Amortization	(4,278)	(4,217)
Net	1,317	265
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Cost	7,136	3,971
Accumulated Amortization	(3,810)	(3,716)
Net	3,326	255
Distributor Relationships
Finite-Lived Intangible Assets [Line Items]
Cost	377	370
Accumulated Amortization	(360)	(355)
Net	17	$ 15
Trade Name
Finite-Lived Intangible Assets [Line Items]
Cost	412
Accumulated Amortization	(10)
Net	$ 402

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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