Goodwill and Purchased Intangible Assets (Schedule Of Goodwill By Reportable Segments) (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 30, 2016	Jul. 25, 2015
Goodwill [Roll Forward]
Balance - Beg	$ 24,469	$ 24,239
Goodwill related to Acquisitions	2,562	255
Goodwill related to divestitures	(141)	0
Other	(265)	(25)
Balance - End	26,625	24,469
Americas
Goodwill [Roll Forward]
Balance - Beg	15,212	15,080
Goodwill related to Acquisitions	1,607	145
Goodwill related to divestitures	(126)	0
Other	(164)	(13)
Balance - End	16,529	15,212
EMEA
Goodwill [Roll Forward]
Balance - Beg	5,791	5,715
Goodwill related to Acquisitions	554	84
Goodwill related to divestitures	(12)	0
Other	(64)	(8)
Balance - End	6,269	5,791
APJC
Goodwill [Roll Forward]
Balance - Beg	3,466	3,444
Goodwill related to Acquisitions	401	26
Goodwill related to divestitures	(3)	0
Other	(37)	(4)
Balance - End	$ 3,827	$ 3,466

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
-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
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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 (f)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 350
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-Paragraph 1
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