Commitments and Contingencies (Schedule of Other Commitments) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2016	Apr. 25, 2015	Apr. 30, 2016	Apr. 25, 2015
Acquisition
Contingency [Line Items]
Compensation expense related to acquisitions	$ 68	$ 72	$ 212	$ 264

Amount of payroll tax expense, compensation, postemployment and benefit-related expenses not elsewhere specified in the taxonomy (such as health plan, profit sharing, incentives, tuition reimbursement, other fringe benefits and perquisites) incurred in the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Name:	us-gaap_OtherLaborRelatedExpenses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration