Segment Information and Major Customers - Summary of Reportable Segments (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 26, 2019	Oct. 27, 2018
Segment Reporting Information [Line Items]
Revenue, total	$ 13,159	$ 13,072
Gross margin	8,464	8,146
Operating segments
Segment Reporting Information [Line Items]
Gross margin	8,676	8,341
Operating segments \| Americas
Segment Reporting Information [Line Items]
Revenue, total	7,977	7,751
Gross margin	5,316	5,070
Operating segments \| EMEA
Segment Reporting Information [Line Items]
Revenue, total	3,283	3,224
Gross margin	2,166	2,070
Operating segments \| APJC
Segment Reporting Information [Line Items]
Revenue, total	1,899	2,096
Gross margin	1,194	1,200
Unallocated corporate items
Segment Reporting Information [Line Items]
Gross margin	$ (212)	$ (195)

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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