Restructuring and Other Charges - Schedule of Activities Related to Restructuring and Other Charges (Details) - USD ($) $ in Millions	3 Months Ended
	Oct. 26, 2019	Oct. 27, 2018
Restructuring Reserve [Roll Forward]
Liability as of beginning period	$ 33	$ 73
Charges	184	78
Cash payments	(155)	(64)
Non-cash items	(15)	(23)
Liability as of ending period	47	64
FISCAL 2017 AND PRIOR PLANS | Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period	0	41
Charges	0	0
Cash payments	0	(10)
Non-cash items	0	0
Liability as of ending period	0	31
FISCAL 2017 AND PRIOR PLANS | Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period	5	13
Charges	0	0
Cash payments	0	(1)
Non-cash items	(2)	0
Liability as of ending period	3	12
FISCAL 2018 PLAN
Restructuring Reserve [Roll Forward]
Charges	184
FISCAL 2018 PLAN | Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period	22	19
Charges	175	54
Cash payments	(154)	(52)
Non-cash items	0	0
Liability as of ending period	43	21
FISCAL 2018 PLAN | Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period	6	0
Charges	9	24
Cash payments	(1)	(1)
Non-cash items	(13)	(23)
Liability as of ending period	$ 1	$ 0