Segment Information and Major Customers - Summary of Reportable Segments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 25, 2020	Apr. 27, 2019	Apr. 25, 2020	Apr. 27, 2019
Segment Reporting Information [Line Items]
Revenue, total	$ 11,983	$ 12,958	$ 37,147	$ 38,476
Gross margin	7,771	8,173	23,999	24,092
Americas
Segment Reporting Information [Line Items]
Revenue, total	7,116	7,695	22,106	22,798
EMEA
Segment Reporting Information [Line Items]
Revenue, total	3,136	3,356	9,553	9,803
APJC
Segment Reporting Information [Line Items]
Revenue, total	1,730	1,907	5,489	5,875
Operating segments
Segment Reporting Information [Line Items]
Gross margin	7,986	8,370	24,636	24,686
Operating segments \| Americas
Segment Reporting Information [Line Items]
Gross margin	4,828	5,046	14,836	14,911
Operating segments \| EMEA
Segment Reporting Information [Line Items]
Gross margin	2,061	2,166	6,289	6,307
Operating segments \| APJC
Segment Reporting Information [Line Items]
Gross margin	1,098	1,158	3,511	3,467
Unallocated corporate items
Segment Reporting Information [Line Items]
Gross margin	$ (215)	$ (197)	$ (637)	$ (594)

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

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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
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-Name Accounting Standards Codification
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