Acquisitions and Divestitures (Summary Of Allocation Of Total Purchase Consideration) (Details) $ in Millions	3 Months Ended
Oct. 29, 2016 USD ($)
Business Acquisition [Line Items]
Purchase Consideration	$ 258
Purchased Intangible Assets	41
Goodwill	217
CloudLock Inc
Business Acquisition [Line Items]
Purchase Consideration	249
Purchased Intangible Assets	36
Goodwill	213
Others (two in total)
Business Acquisition [Line Items]
Purchase Consideration	9
Purchased Intangible Assets	5
Goodwill	$ 4

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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-Name Accounting Standards Codification
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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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