Goodwill and Purchased Intangible Assets - Schedule of Goodwill by Reportable Segments (Details) $ in Millions	9 Months Ended
Apr. 25, 2020 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 33,529
Acquisitions	130
Foreign currency translation and Other	(206)
Ending Balance	33,453
Americas
Goodwill [Roll Forward]
Beginning Balance	21,120
Acquisitions	88
Foreign currency translation and Other	(128)
Ending Balance	21,080
EMEA
Goodwill [Roll Forward]
Beginning Balance	7,977
Acquisitions	26
Foreign currency translation and Other	(50)
Ending Balance	7,953
APJC
Goodwill [Roll Forward]
Beginning Balance	4,432
Acquisitions	16
Foreign currency translation and Other	(28)
Ending Balance	$ 4,420

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
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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 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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