Business Acquisitions - Schedule of Purchased Intangible Assets, Atmel (Details) - Atmel Corporation $ in Millions	Apr. 04, 2016 USD ($)
Business Acquisition [Line Items]
Useful life (in years)	9 years
Purchased intangible assets	$ 1,888.4
Core/developed technology
Business Acquisition [Line Items]
Useful life (in years)	11 years
Purchased intangible assets	$ 1,075.0
Customer-related
Business Acquisition [Line Items]
Useful life (in years)	6 years
Purchased intangible assets	$ 630.6
Backlog
Business Acquisition [Line Items]
Useful life (in years)	1 year
Purchased intangible assets	$ 40.3
Other intangible assets
Business Acquisition [Line Items]
Useful life (in years)	5 years
Purchased intangible assets	$ 1.8
In-process research and development
Business Acquisition [Line Items]
In-process research and development	$ 140.7

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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