Segment Information and Major Customers (Additional Information) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jan. 26, 2019 USD ($)	Jan. 27, 2018 USD ($)	Jan. 26, 2019 USD ($) segment	Jan. 27, 2018 USD ($)
Segment Reporting Information [Line Items]
Number of geographic segments (segment) \| segment			3
Revenue	$ 12,446	$ 11,887	$ 25,518	$ 24,023
United States
Segment Reporting Information [Line Items]
Revenue	$ 6,400	$ 6,100	$ 13,300	$ 12,600

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

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