Segment Information and Major Customers (Summary Of Reportable Segments) (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 30, 2016	Jul. 25, 2015	Jul. 26, 2014
Segment Reporting Information [Line Items]
Revenue:	$ 49,247	$ 49,161	$ 47,142
Gross margin:	30,960	29,681	27,769
Unallocated corporate items
Segment Reporting Information [Line Items]
Gross margin:	(644)	(1,001)	(1,562)
Americas
Segment Reporting Information [Line Items]
Revenue:	29,411	29,655	27,781
Gross margin:	19,006	18,670	17,379
EMEA
Segment Reporting Information [Line Items]
Revenue:	12,281	12,322	12,006
Gross margin:	7,976	7,705	7,700
APJC
Segment Reporting Information [Line Items]
Revenue:	7,555	7,184	7,355
Gross margin:	4,622	4,307	4,252
Segment total
Segment Reporting Information [Line Items]
Gross margin:	$ 31,604	$ 30,682	$ 29,331

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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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=26872669&loc=d3e20235-122688

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