Income Taxes - Statutory Federal Income Tax Rate (Detail) - USD ($) $ in Millions	12 Months Ended
Apr. 29, 2016	Apr. 24, 2015	Apr. 25, 2014
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Tax computed at federal statutory rate	$ 121	$ 250	$ 259
State income taxes, net of federal benefit	(3)	5	6
Foreign earnings in lower tax jurisdictions	(81)	(141)	(163)
Stock-based compensation	13	6	10
Research and development credits	(14)	(14)	(9)
Resolution of income tax examinations	20	46	0
Domestic production activities deduction	(10)	(5)	(6)
Other	6	6	6
Provision for income taxes	116	153	103
SolidFire
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Tax charge from integration of intellectual properties from the SolidFire acquisition	$ 64	$ 0	$ 0

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of the difference between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for qualified production activity.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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