Segment Information and Major Customers (Summary Of Reportable Segments) (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 29, 2016	Oct. 24, 2015
Segment Reporting Information [Line Items]
Revenue, total	$ 12,352	$ 12,682
Gross margin	7,884	7,832
Americas
Segment Reporting Information [Line Items]
Revenue, total	7,443	7,792
Gross margin	4,833	4,943
EMEA
Segment Reporting Information [Line Items]
Revenue, total	3,013	3,094
Gross margin	2,013	1,989
APJC
Segment Reporting Information [Line Items]
Revenue, total	1,896	1,796
Gross margin	1,204	1,078
Segment Reconciling Items
Segment Reporting Information [Line Items]
Gross margin	8,050	8,010
Intersegment Eliminations
Segment Reporting Information [Line Items]
Gross margin	$ (166)	$ (178)

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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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ 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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