Goodwill and Acquired Intangibles (Details 1) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross carrying amount		$ 517,137
Accumulated amortization	$ (333,682)	(364,262)
Acquired intangibles, net	227,753	152,875
In-process technology		19,500
Intangible Assets, Gross (Excluding Goodwill)	561,435	536,637
Intangible Assets, Net (Excluding Goodwill)	227,753	172,375
Existing Technology [Member]
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross carrying amount	370,834	363,142
Accumulated amortization	(218,553)	(245,902)
Acquired intangibles, net	152,281	117,240
Agreements and Relationships [Member]
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross carrying amount	180,011	146,395
Accumulated amortization	(108,736)	(112,565)
Acquired intangibles, net	71,275	33,830
Tradenames Trademarks And Patents [Member]
Acquired intangibles with finite lives, excluding intangibles fully amortized at end of prior fiscal year
Gross carrying amount	10,590	7,600
Accumulated amortization	(6,393)	(5,795)
Acquired intangibles, net	$ 4,197	$ 1,805

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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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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-Name Accounting Standards Codification
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