Goodwill and Purchased Intangible Assets (Schedule of Goodwill by Reportable Segments) (Details) $ in Millions	6 Months Ended
Jan. 26, 2019 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 31,706
Acquisitions & Divestitures	1,701
Other	(114)
Ending Balance	33,293
Americas
Goodwill [Roll Forward]
Beginning Balance	19,998
Acquisitions & Divestitures	1,082
Other	(79)
Ending Balance	21,001
EMEA
Goodwill [Roll Forward]
Beginning Balance	7,529
Acquisitions & Divestitures	429
Other	(22)
Ending Balance	7,936
APJC
Goodwill [Roll Forward]
Beginning Balance	4,179
Acquisitions & Divestitures	190
Other	(13)
Ending Balance	$ 4,356

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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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments 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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