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Restructuring and Other Charges - Schedule of Activities Related to Restructuring and Other Charges (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Apr. 25, 2020	Apr. 25, 2020	Apr. 27, 2019
Restructuring Reserve [Roll Forward]
Liability as of beginning period		$ 33	$ 73
Charges		354	282
Cash payments		(260)	(275)
Non-cash items		(29)	(46)
Liability as of ending period	$ 98	98	34
FISCAL 2018 AND PRIOR PLANS \| Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period		22
Charges		209
Cash payments		(217)
Non-cash items		0
Liability as of ending period	14	14
FISCAL 2018 AND PRIOR PLANS \| Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period		11
Charges		17
Cash payments		(2)
Non-cash items		(23)
Liability as of ending period	3	3
FISCAL 2020 PLAN
Restructuring Reserve [Roll Forward]
Charges	128	128
FISCAL 2020 PLAN \| Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period		0
Charges		116
Cash payments		(35)
Non-cash items		0
Liability as of ending period	81	81
FISCAL 2020 PLAN \| Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period		0
Charges		12
Cash payments		(6)
Non-cash items		(6)
Liability as of ending period	$ 0	0
FISCAL 2017 AND PRIOR PLANS \| Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period			41
Charges			0
Cash payments			(34)
Non-cash items			0
Liability as of ending period			7
FISCAL 2017 AND PRIOR PLANS \| Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period			13
Charges			(1)
Cash payments			(7)
Non-cash items			0
Liability as of ending period			5
FISCAL 2018 PLAN
Restructuring Reserve [Roll Forward]
Charges		$ 226
FISCAL 2018 PLAN \| Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period			19
Charges			232
Cash payments			(232)
Non-cash items			0
Liability as of ending period			19
FISCAL 2018 PLAN \| Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period			0
Charges			51
Cash payments			(2)
Non-cash items			(46)
Liability as of ending period			$ 3