Balance Sheet and Other Details - Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Millions	Oct. 30, 2021	Jul. 31, 2021	Oct. 24, 2020	Jul. 25, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash and cash equivalents	$ 7,619	$ 9,175
Restricted cash included in other current assets	10	14
Restricted cash included in other assets	750	753
Total cash, cash equivalents, and restricted cash	$ 8,379	$ 9,942	$ 10,825	$ 11,812

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3521-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=123431023&loc=SL98516268-108586

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