Goodwill and Purchased Intangible Assets, Net - Purchased Intangible Assets, Net (Detail) (USD $) In Millions, unless otherwise specified	Apr. 24, 2015	Apr. 25, 2014
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	$ 320.3	$ 297.1
Accumulated Amortization	(230.8)	(175.6)
Net Assets	89.5us-gaap_FiniteLivedIntangibleAssetsNet	121.5us-gaap_FiniteLivedIntangibleAssetsNet
Developed Technology
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	312.4	283.0
Accumulated Amortization	(225.2)	(162.6)
Net Assets	87.2	120.4
Customer Contracts/Relationships
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	5.0	9.6
Accumulated Amortization	(2.7)	(9.0)
Net Assets	2.3	0.6
Other Purchased Intangibles
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	2.9	4.5
Accumulated Amortization	(2.9)	(4.0)
Net Assets	$ 0	$ 0.5

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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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- Definition

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

+ References

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+ References

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