Commitments and Contingencies (Schedule Of Product Warranty Liability) (Details) - USD ($) $ in Millions	9 Months Ended
Apr. 30, 2016	Apr. 25, 2015
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Balance at beginning of period	$ 449	$ 446
Provision for warranties issued	512	517
Payments	(524)	(512)
Balance at end of period	409	451
Divestitures
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Divestitures	$ (28)	$ 0

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

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(5))
-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.

+ References

+ Details

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- Definition

Total increases or decreases in the standard and extended product warranty liability during the period.

+ References

+ Details

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- Definition

Represents the aggregate increase in the liability for accruals related to standard and extended product warranties issued during the reporting period.

+ References

+ Details

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