Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 29, 2017	Jul. 30, 2016	Jul. 25, 2015
Financing Receivables
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of fiscal year	$ 375	$ 382	$ 349
Provisions	(35)	17	57
Recoveries (write-offs), net	(49)	(15)	(7)
Foreign exchange and other	4	(9)	(17)
Balance at end of fiscal year	295	375	382
Accounts Receivable
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of fiscal year	249	302	265
Provisions	27	(26)	77
Recoveries (write-offs), net	(61)	(28)	(40)
Foreign exchange and other	(4)	1	0
Balance at end of fiscal year	$ 211	$ 249	$ 302

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of increase (decrease) in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from adjustments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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Total of 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 established to represent expected future costs.

+ References

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Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

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Total of the deductions 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 established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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