Goodwill and Purchased Intangible Assets (Schedule of Goodwill by Reportable Segments) (Details) $ in Millions	9 Months Ended
Apr. 27, 2019 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 31,706
Acquisitions & Divestitures	2,000
Other	(162)
Ending Balance	33,544
Americas
Goodwill [Roll Forward]
Beginning Balance	19,998
Acquisitions & Divestitures	1,240
Other	(109)
Ending Balance	21,129
EMEA
Goodwill [Roll Forward]
Beginning Balance	7,529
Acquisitions & Divestitures	486
Other	(33)
Ending Balance	7,982
APJC
Goodwill [Roll Forward]
Beginning Balance	4,179
Acquisitions & Divestitures	274
Other	(20)
Ending Balance	$ 4,433

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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