Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 30, 2016	Jul. 25, 2015	Jul. 26, 2014
Financing Receivables
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of fiscal year	$ 382	$ 349	$ 344
Provisions	17	57	14
Recoveries (write-offs), net	(15)	(7)	(9)
Foreign exchange and other	9	17
Balance at end of fiscal year	375	382	349
Accounts Receivable
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of fiscal year	302	265	228
Provisions	(26)	77	65
Recoveries (write-offs), net	(28)	(40)	(28)
Foreign exchange and other	1	0
Balance at end of fiscal year	$ 249	$ 302	$ 265

Total of the adjustments in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 09
-Article 12

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