Goodwill and Purchased Intangible Assets (Schedule Of Goodwill By Reportable Segments) (Details) $ in Millions	9 Months Ended
Apr. 29, 2017 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 26,625
Acquisitions	2,865
Other	26
Ending Balance	29,516
Americas
Goodwill [Roll Forward]
Beginning Balance	16,529
Acquisitions	1,986
Other	13
Ending Balance	18,528
EMEA
Goodwill [Roll Forward]
Beginning Balance	6,269
Acquisitions	724
Other	8
Ending Balance	7,001
APJC
Goodwill [Roll Forward]
Beginning Balance	3,827
Acquisitions	155
Other	5
Ending Balance	$ 3,987

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
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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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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-Section 25
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-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e961-128460

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