Segment Information and Major Customers (Summary Of Reportable Segments) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2016	Apr. 25, 2015	Apr. 30, 2016	Apr. 25, 2015
Segment Reporting Information [Line Items]
Revenue, total	$ 12,000	$ 12,137	$ 36,609	$ 36,318
Gross margin	7,721	7,525	22,985	21,948
Unallocated corporate items
Segment Reporting Information [Line Items]
Gross margin	(99)	(64)	(451)	(759)
Americas
Segment Reporting Information [Line Items]
Revenue, total	7,062	7,252	21,773	21,854
Gross margin	4,684	4,560	14,046	13,776
EMEA
Segment Reporting Information [Line Items]
Revenue, total	3,001	3,119	9,176	9,212
Gross margin	1,966	1,949	5,953	5,774
APJC
Segment Reporting Information [Line Items]
Revenue, total	1,937	1,766	5,660	5,252
Gross margin	1,170	1,080	3,437	3,157
Consolidated by Segment
Segment Reporting Information [Line Items]
Revenue, total	12,000	12,137	36,609	36,318
Total by Segment
Segment Reporting Information [Line Items]
Gross margin	$ 7,820	$ 7,589	$ 23,436	$ 22,707

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=26872669&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=26872669&loc=d3e20235-122688

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