Goodwill and Purchased Intangible Assets (Schedule of Goodwill by Reportable Segments) (Details) $ in Millions	3 Months Ended
Oct. 27, 2018 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 31,706
Acquisitions	1,763
Other	(83)
Ending Balance	33,386
Americas
Goodwill [Roll Forward]
Beginning Balance	19,998
Acquisitions	1,073
Other	(53)
Ending Balance	21,018
EMEA
Goodwill [Roll Forward]
Beginning Balance	7,529
Acquisitions	491
Other	(19)
Ending Balance	8,001
APJC
Goodwill [Roll Forward]
Beginning Balance	4,179
Acquisitions	199
Other	(11)
Ending Balance	$ 4,367

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 in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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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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