Intangible Assets Intangible Assets - Schedule of Finite-Lived Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Apr. 04, 2015	Jan. 03, 2015
Finite-Lived Intangible Assets [Line Items]
Total cost	$ 41,256	$ 40,786
Total accumulated amortization	(13,901)	(13,015)
Net carrying amount	27,355us-gaap_FiniteLivedIntangibleAssetsNet	27,771us-gaap_FiniteLivedIntangibleAssetsNet
Patents
Finite-Lived Intangible Assets [Line Items]
Total cost	20,755	20,459
Total accumulated amortization	(6,988)	(6,649)
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Total cost	7,669	7,669
Total accumulated amortization	(2,045)	(1,853)
Acquired technology
Finite-Lived Intangible Assets [Line Items]
Total cost	5,580	5,580
Total accumulated amortization	(1,531)	(1,392)
Trademarks
Finite-Lived Intangible Assets [Line Items]
Total cost	3,681	3,562
Total accumulated amortization	(924)	(866)
Capitalized software development costs
Finite-Lived Intangible Assets [Line Items]
Total cost	2,066	2,066
Total accumulated amortization	(1,477)	(1,440)
Other
Finite-Lived Intangible Assets [Line Items]
Total cost	1,505	1,450
Total accumulated amortization	$ (936)	$ (815)

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

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