Restructuring and Other Charges - Schedule of Activities Related to Restructuring and Other Charges (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jan. 25, 2020	Jan. 25, 2020	Jan. 26, 2019
Restructuring Reserve [Roll Forward]
Liability as of beginning period		$ 33	$ 73
Charges		226	264
Cash payments		(203)	(237)
Non-cash items		(23)	(42)
Liability as of ending period	$ 33	33	58
FISCAL 2017 AND PRIOR PLANS | Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period		0	41
Charges		0	0
Cash payments		0	(31)
Non-cash items		0	0
Liability as of ending period	0	0	10
FISCAL 2017 AND PRIOR PLANS | Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period		5	13
Charges		0	(1)
Cash payments		0	(3)
Non-cash items		(2)	0
Liability as of ending period	3	3	9
FISCAL 2018 PLAN
Restructuring Reserve [Roll Forward]
Charges	42	226
FISCAL 2018 PLAN | Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period		22	19
Charges		209	222
Cash payments		(202)	(202)
Non-cash items		0	0
Liability as of ending period	29	29	39
FISCAL 2018 PLAN | Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period		6	0
Charges		17	43
Cash payments		(1)	(1)
Non-cash items		(21)	(42)
Liability as of ending period	$ 1	$ 1	$ 0