Goodwill and Purchased Intangible Assets - Schedule of Goodwill by Reportable Segments (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 27, 2019	Jul. 28, 2018
Goodwill [Roll Forward]
Beginning balance	$ 31,706	$ 29,766
Acquisitions & Divestitures	2,000	2,017
Other	(177)	(77)
Ending balance	33,529	31,706
Americas
Goodwill [Roll Forward]
Beginning balance	19,998	18,691
Acquisitions & Divestitures	1,240	1,355
Other	(118)	(48)
Ending balance	21,120	19,998
EMEA
Goodwill [Roll Forward]
Beginning balance	7,529	7,057
Acquisitions & Divestitures	486	491
Other	(38)	(19)
Ending balance	7,977	7,529
APJC
Goodwill [Roll Forward]
Beginning balance	4,179	4,018
Acquisitions & Divestitures	274	171
Other	(21)	(10)
Ending balance	$ 4,432	$ 4,179

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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