Segment Information and Major Customers (Summary Of Reportable Segments) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 29, 2017	Apr. 30, 2016	Apr. 29, 2017	Apr. 30, 2016
Segment Reporting Information [Line Items]
Revenue, total	$ 11,940	$ 12,000	$ 35,872	$ 36,609
Gross margin	7,518	7,721	22,678	22,985
Operating Segments \| Americas
Segment Reporting Information [Line Items]
Revenue, total	7,046	7,056	21,149	21,759
Gross margin	4,551	4,677	13,672	14,031
Operating Segments \| EMEA
Segment Reporting Information [Line Items]
Revenue, total	2,999	3,006	9,077	9,193
Gross margin	1,963	1,970	5,988	5,970
Operating Segments \| APJC
Segment Reporting Information [Line Items]
Revenue, total	1,895	1,938	5,646	5,657
Gross margin	1,171	1,173	3,496	3,435
Segment Reconciling Items
Segment Reporting Information [Line Items]
Gross margin	7,685	7,820	23,156	23,436
Intersegment Eliminations
Segment Reporting Information [Line Items]
Gross margin	$ (167)	$ (99)	$ (478)	$ (451)

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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