Goodwill and Purchased Intangible Assets - Schedule of Goodwill by Reportable Segments (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 25, 2020	Jul. 27, 2019
Goodwill [Roll Forward]
Beginning balance	$ 33,529	$ 31,706
Acquisitions & Divestitures	198	2,000
Foreign Currency Translation and Other	79	(177)
Ending balance	33,806	33,529
Americas
Goodwill [Roll Forward]
Beginning balance	21,120	19,998
Acquisitions & Divestitures	132	1,240
Foreign Currency Translation and Other	52	(118)
Ending balance	21,304	21,120
EMEA
Goodwill [Roll Forward]
Beginning balance	7,977	7,529
Acquisitions & Divestitures	44	486
Foreign Currency Translation and Other	19	(38)
Ending balance	8,040	7,977
APJC
Goodwill [Roll Forward]
Beginning balance	4,432	4,179
Acquisitions & Divestitures	22	274
Foreign Currency Translation and Other	8	(21)
Ending balance	$ 4,462	$ 4,432

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
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-Section S99
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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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