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.

No definition available.

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- Definition

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
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- References

No definition available.

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- Definition

The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

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Acquisitions and Divestitures (Acquisitions Narrative) (Details) $ in Millions		12 Months Ended
	Jul. 31, 2017 USD ($)	Jul. 29, 2017 USD ($) acquisition	Jul. 30, 2016 USD ($)	Jul. 25, 2015 USD ($)
Business Combinations [Abstract]
Number of business combinations (acquisition) \| acquisition		7
Cash and cash equivalents acquired		$ 138	$ 44	$ 5
Business Acquisition [Line Items]
Total consideration		$ 3,637	$ 3,378	$ 334
Subsequent Event \| Viptela, Inc.
Business Acquisition [Line Items]
Total consideration	$ 610