Goodwill and Purchased Intangible Assets - Schedule of Goodwill by Reportable Segments (Details) $ in Millions	3 Months Ended
Oct. 24, 2020 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 33,806
Acquisitions	666
Foreign Currency Translation and Other	63
Ending Balance	34,535
Americas
Goodwill [Roll Forward]
Beginning Balance	21,304
Acquisitions	393
Foreign Currency Translation and Other	40
Ending Balance	21,737
EMEA
Goodwill [Roll Forward]
Beginning Balance	8,040
Acquisitions	183
Foreign Currency Translation and Other	15
Ending Balance	8,238
APJC
Goodwill [Roll Forward]
Beginning Balance	4,462
Acquisitions	90
Foreign Currency Translation and Other	8
Ending Balance	$ 4,560

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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