Goodwill and Purchased Intangible Assets, Net - Purchased Intangible Assets, Net (Detail) - USD ($) $ in Millions	Oct. 27, 2017	Apr. 28, 2017
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	$ 216	$ 200
Accumulated Amortization	(96)	(69)
Net Assets	120	131
Developed Technology
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	164	148
Accumulated Amortization	(61)	(44)
Net Assets	103	104
Customer Contracts/Relationships
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	43	43
Accumulated Amortization	(27)	(19)
Net Assets	16	24
Other Purchased Intangibles
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	9	9
Accumulated Amortization	(8)	(6)
Net Assets	$ 1	$ 3