Goodwill and Purchased Intangible Assets (Schedule of Goodwill by Reportable Segments) (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 28, 2018	Jul. 29, 2017
Goodwill [Roll Forward]
Beginning balance	$ 29,766	$ 26,625
Acquisitions	2,017	2,945
Other	(77)	196
Ending balance	31,706	29,766
Americas
Goodwill [Roll Forward]
Beginning balance	18,691	16,529
Acquisitions	1,355	2,042
Other	(48)	120
Ending balance	19,998	18,691
EMEA
Goodwill [Roll Forward]
Beginning balance	7,057	6,269
Acquisitions	491	740
Other	(19)	48
Ending balance	7,529	7,057
APJC
Goodwill [Roll Forward]
Beginning balance	4,018	3,827
Acquisitions	171	163
Other	(10)	28
Ending balance	$ 4,179	$ 4,018

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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