Goodwill and Purchased Intangible Assets, Net - Purchased Intangible Assets, Net (Detail) - USD ($) $ in Millions	Apr. 24, 2020	Apr. 26, 2019
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	$ 196	$ 201
Accumulated Amortization	(152)	(154)
Net Assets	44	47
Developed Technology
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	192	160
Accumulated Amortization	(152)	(113)
Net Assets	40	47
Customer Contracts/Relationships
Acquired Finite Lived Intangible Assets [Line Items]
Gross Assets	4	41
Accumulated Amortization	0	(41)
Net Assets	$ 4	$ 0