Restructuring and Other Charges (Schedule Of Activities Related To Restructuring And Other Charges) (Details) - USD ($) $ in Millions	3 Months Ended
	Oct. 29, 2016	Oct. 24, 2015
Restructuring Reserve [Roll Forward]
Liability as of beginning period	$ 45	$ 89
Charges	411	142
Cash payments	(270)	(129)
Non-cash items	(47)	(16)
Liability as of ending period	139	86
FISCAL 2015 AND PRIOR PLANS | Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period	21	60
Charges	0	125
Cash payments	(12)	(123)
Non-cash items	(4)	0
Liability as of ending period	5	62
FISCAL 2015 AND PRIOR PLANS | Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period	24	29
Charges	0	17
Cash payments	0	(6)
Non-cash items	(2)	(16)
Liability as of ending period	22	$ 24
FISCAL 2017 PLAN | Employee Severance
Restructuring Reserve [Roll Forward]
Liability as of beginning period	0
Charges	369
Cash payments	(257)
Non-cash items	0
Liability as of ending period	112
FISCAL 2017 PLAN | Other
Restructuring Reserve [Roll Forward]
Liability as of beginning period	0
Charges	42
Cash payments	(1)
Non-cash items	(41)
Liability as of ending period	$ 0