Intangible Assets Intangible Assets - Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Total cost	$ 50,785	$ 50,689
Total accumulated amortization	(21,994)	(21,313)
Intangible assets, net	28,791	29,376
Patents
Finite-Lived Intangible Assets [Line Items]
Total cost	19,942	19,950
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Total cost	7,669	7,669
Licensing Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Total cost	7,500	7,500
Acquired technology
Finite-Lived Intangible Assets [Line Items]
Total cost	5,580	5,580
Trademarks
Finite-Lived Intangible Assets [Line Items]
Total cost	3,881	3,777
Capitalized software development costs
Finite-Lived Intangible Assets [Line Items]
Total cost	2,539	2,539
Other
Finite-Lived Intangible Assets [Line Items]
Total cost	$ 3,674	$ 3,674

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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