Commitments and Contingencies - Additional Information (Detail) - USD ($)	3 Months Ended
	Jul. 31, 2015	Jul. 25, 2014	Apr. 24, 2015
Commitments and Contingencies Disclosure [Line Items]
Future annual minimum lease payments	$ 205,000,000
Accrued purchase commitments with contract manufacturers	16,000,000		$ 17,000,000
Sale of finance receivables	42,000,000	$ 52,000,000
Legal proceedings and claims	$ 0
Maximum
Commitments and Contingencies Disclosure [Line Items]
Terms of recourse leases	3 years
Inventory
Commitments and Contingencies Disclosure [Line Items]
Purchase orders and other commitments	$ 262,000,000
Construction Related
Commitments and Contingencies Disclosure [Line Items]
Purchase orders and other commitments	45,000,000
Other
Commitments and Contingencies Disclosure [Line Items]
Purchase orders and other commitments	$ 178,000,000