Goodwill and Acquired Intangibles (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Apr. 04, 2015	Jan. 03, 2015
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross carrying amount	511,863	$ 514,146
Accumulated amortization	(169,013)	(154,814)
Acquired intangibles, net	342,850us-gaap_FiniteLivedIntangibleAssetsNet	359,332us-gaap_FiniteLivedIntangibleAssetsNet
In-process technology	1,600	1,600
Intangible assets, gross (excluding goodwill)	513,463	515,746
Intangible assets, net (excluding goodwill)	344,450	360,932
Existing Technology [Member]
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross carrying amount	328,119	328,325
Accumulated amortization	(94,617)	(84,822)
Acquired intangibles, net	233,502	243,503
Agreements and relationships [Member]
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross carrying amount	173,625	175,202
Accumulated amortization	(69,979)	(65,512)
Acquired intangibles, net	103,646	109,690
Tradenames Trademarks And Patents [Member]
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross carrying amount	10,119	10,619
Accumulated amortization	(4,417)	(4,480)
Acquired intangibles, net	5,702	$ 6,139
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Expected time for completion of in-process research and development	6 months
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Expected time for completion of in-process research and development	9 months

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- Definition

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

+ References

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.

+ References

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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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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount before accumulated amortization of intangible assets, excluding goodwill.

+ References

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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-Name Accounting Standards Codification

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-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph ((a)(1),(b))

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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