Goodwill and Purchased Intangible Assets - Schedule of Purchased Intangible Assets With Finite and Indefinite Lives (Details) - USD ($) $ in Millions	Apr. 25, 2020	Jul. 27, 2019
Purchased intangible assets with finite lives:
Gross	$ 4,146	$ 4,151
Accumulated Amortization	(2,615)	(2,286)
Total purchased intangible assets with finite lives, net	1,531	1,865
In-process research and development, with indefinite lives	213	336
Total finite and indefinite lives intangible assets, gross	4,359	4,487
Total finite and indefinite lives intangible assets, net	1,744	2,201
TECHNOLOGY
Purchased intangible assets with finite lives:
Gross	3,362	3,270
Accumulated Amortization	(2,261)	(1,933)
Total purchased intangible assets with finite lives, net	1,101	1,337
CUSTOMER RELATIONSHIPS
Purchased intangible assets with finite lives:
Gross	758	840
Accumulated Amortization	(336)	(331)
Total purchased intangible assets with finite lives, net	422	509
OTHER
Purchased intangible assets with finite lives:
Gross	26	41
Accumulated Amortization	(18)	(22)
Total purchased intangible assets with finite lives, net	$ 8	$ 19