Goodwill and Purchased Intangible Assets (Schedule Of Goodwill By Reportable Segments) (Details) $ in Millions	3 Months Ended
Oct. 29, 2016 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 26,625
Acquisitions	217
Other	(19)
Ending Balance	26,823
Americas
Goodwill [Roll Forward]
Beginning Balance	16,529
Acquisitions	132
Other	(13)
Ending Balance	16,648
EMEA
Goodwill [Roll Forward]
Beginning Balance	6,269
Acquisitions	62
Other	(4)
Ending Balance	6,327
APJC
Goodwill [Roll Forward]
Beginning Balance	3,827
Acquisitions	23
Other	(2)
Ending Balance	$ 3,848

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e961-128460

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