Financial Instruments (Schedule Of Changes In Cash Flow Hedges In Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 29, 2018	Apr. 30, 2017	Apr. 29, 2018	Apr. 30, 2017
Derivative Instruments, Gain Loss [Line Items]
OCI before tax accumulated derivative gain (loss) beginning of period	$ (22)	$ (27)	$ (34)	$ (64)
OCI before tax accumulated derivative gain (loss) end of period	(10)	(23)	(10)	(23)
Foreign Exchange Forward Contracts [Member]
Derivative Instruments, Gain Loss [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	6	7	7	8
Foreign Exchange Forward Contracts [Member] \| Cost Of Products Sold [Member]
Derivative Instruments, Gain Loss [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	0	1	0	5
Foreign Exchange Forward Contracts [Member] \| Other Expenses/Income [Member]
Derivative Instruments, Gain Loss [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	0	0	0	1
Interest Rate Contract [Member]
Derivative Instruments, Gain Loss [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	5	(5)	15	24
Interest Rate Contract [Member] \| Interest Expense [Member]
Derivative Instruments, Gain Loss [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ 1	$ 1	$ 2	$ 3

Accumulated balance, before tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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