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

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Segment Information and Major Customers - Summary of Reportable Segments (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Jul. 27, 2019	Apr. 27, 2019	Jan. 26, 2019	Oct. 27, 2018	Jul. 28, 2018	Apr. 28, 2018	Jan. 27, 2018	Oct. 28, 2017	Jul. 27, 2019	Jul. 28, 2018	Jul. 29, 2017
Segment Reporting Information [Line Items]
Revenue	$ 13,428	$ 12,958	$ 12,446	$ 13,072	$ 12,844	$ 12,463	$ 11,887	$ 12,136	$ 51,904	$ 49,330	$ 48,005
Gross margin	$ 8,574	$ 8,173	$ 7,773	$ 8,146	$ 7,922	$ 7,759	$ 7,498	$ 7,427	32,666	30,606	30,224
Operating Segments
Segment Reporting Information [Line Items]
Gross margin									33,479	31,463	30,880
Operating Segments \| Americas
Segment Reporting Information [Line Items]
Revenue									30,927	29,070	28,351
Gross margin									20,338	18,792	18,284
Operating Segments \| EMEA
Segment Reporting Information [Line Items]
Revenue									13,100	12,425	12,004
Gross margin									8,457	7,945	7,855
Operating Segments \| APJC
Segment Reporting Information [Line Items]
Revenue									7,877	7,834	7,650
Gross margin									4,683	4,726	4,741
Unallocated corporate items
Segment Reporting Information [Line Items]
Gross margin									$ (813)	$ (857)	$ (656)