Segment Information and Major Customers - Summary of Reportable Segments (Details) - USD ($) $ in Millions	3 Months Ended
	Oct. 24, 2020	Oct. 26, 2019
Segment Reporting Information [Line Items]
Revenue	$ 11,929	$ 13,159
Gross margin	7,581	8,464
Operating segments
Segment Reporting Information [Line Items]
Gross margin	7,853	8,676
Operating segments | Americas
Segment Reporting Information [Line Items]
Revenue	7,198	7,977
Gross margin	4,847	5,316
Operating segments | EMEA
Segment Reporting Information [Line Items]
Revenue	2,964	3,283
Gross margin	1,894	2,166
Operating segments | APJC
Segment Reporting Information [Line Items]
Revenue	1,767	1,899
Gross margin	1,113	1,194
Unallocated corporate items
Segment Reporting Information [Line Items]
Gross margin	$ (272)	$ (212)