Derivatives and Hedging Activities - Schedule of Derivative Instruments Not Designated as Cash Flow Hedges (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jan. 29, 2016	Jan. 23, 2015	Jan. 29, 2016	Jan. 23, 2015
Foreign Exchange Forward Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Foreign currency exchange contracts	$ 1	$ 11	$ (6)	$ 9

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration