Restructuring and Other Charges (Schedule of Activities Related to Restructuring and Other Charges) (Details) - USD ($) $ in Millions	6 Months Ended
	Jan. 27, 2018	Jan. 28, 2017
Restructuring Reserve [Roll Forward]
Liability as of beginning period	$ 117	$ 45
Charges	250	544
Cash payments	(240)	(388)
Non-cash items	(15)	(73)
Liability as of ending period	112	128
FISCAL 2017 PLAN | Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period	74	21
Charges	223	452
Cash payments	(213)	(381)
Non-cash items	3	(6)
Liability as of ending period	87	86
FISCAL 2017 PLAN | Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period	43	24
Charges	27	92
Cash payments	(27)	(7)
Non-cash items	(18)	(67)
Liability as of ending period	$ 25	$ 42