Purchased Intangible Assets, Net - Amortization Expense for Purchased Intangible Assets (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jan. 29, 2016	Jan. 23, 2015	Jan. 29, 2016	Jan. 23, 2015
Acquired Finite Lived Intangible Assets [Line Items]
Amortization expense	$ 14	$ 19	$ 42	$ 48
Cost of revenues | Developed Technology
Acquired Finite Lived Intangible Assets [Line Items]
Amortization expense	13	18	41	47
Operating expenses | Customer Contracts/Relationships
Acquired Finite Lived Intangible Assets [Line Items]
Amortization expense	$ 1	$ 1	$ 1	$ 1