Segment Information and Major Customers (Summary of Reportable Segments) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 28, 2018	Apr. 29, 2017	Apr. 28, 2018	Apr. 29, 2017
Segment Reporting Information [Line Items]
Revenue, total	$ 12,463	$ 11,940	$ 36,486	$ 35,872
Gross margin	7,759	7,518	22,684	22,678
Operating Segments \| Americas
Segment Reporting Information [Line Items]
Revenue, total	7,161	7,046	21,515	21,149
Gross margin	4,614	4,551	13,950	13,672
Operating Segments \| EMEA
Segment Reporting Information [Line Items]
Revenue, total	3,281	2,999	9,252	9,077
Gross margin	2,109	1,963	5,925	5,988
Operating Segments \| APJC
Segment Reporting Information [Line Items]
Revenue, total	2,021	1,895	5,719	5,646
Gross margin	1,247	1,171	3,506	3,496
Segment Reconciling Items
Segment Reporting Information [Line Items]
Gross margin	7,970	7,685	23,381	23,156
Intersegment Eliminations
Segment Reporting Information [Line Items]
Gross margin	$ (211)	$ (167)	$ (697)	$ (478)

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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