Goodwill and Other Intangible Assets - Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Mar. 29, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, accumulated amortization	$ (29,661)	$ (28,930)
Total intangible assets included in other long-term assets	50,228us-gaap_FiniteLivedIntangibleAssetsNet	54,111us-gaap_FiniteLivedIntangibleAssetsNet
Patents, trademarks and other [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	24,225	25,333
Finite-lived intangible assets, accumulated amortization	(12,734)	(12,805)
Total intangible assets included in other long-term assets	11,491	12,528
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	21,657	21,739
Finite-lived intangible assets, accumulated amortization	(6,187)	(5,863)
Total intangible assets included in other long-term assets	15,470	15,876
Developed technology [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	31,562	33,525
Finite-lived intangible assets, accumulated amortization	(8,295)	(7,818)
Total intangible assets included in other long-term assets	$ 23,267	$ 25,707

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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