Goodwill and Purchased Intangible Assets (Schedule of Goodwill by Reportable Segments) (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 29, 2017	Jul. 30, 2016
Goodwill [Roll Forward]
Beginning balance	$ 26,625	$ 24,469
Acquisitions	2,945	2,562
Divestiture	0	(141)
Other	196	(265)
Ending balance	29,766	26,625
Americas
Goodwill [Roll Forward]
Beginning balance	16,529	15,212
Acquisitions	2,042	1,607
Divestiture	0	(126)
Other	120	(164)
Ending balance	18,691	16,529
EMEA
Goodwill [Roll Forward]
Beginning balance	6,269	5,791
Acquisitions	740	554
Divestiture	0	(12)
Other	48	(64)
Ending balance	7,057	6,269
APJC
Goodwill [Roll Forward]
Beginning balance	3,827	3,466
Acquisitions	163	401
Divestiture	0	(3)
Other	28	(37)
Ending balance	$ 4,018	$ 3,827

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of divestiture 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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