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. 30, 2023	May 01, 2022	Apr. 30, 2023	May 01, 2022
Derivative Instruments, Gain (Loss) [Line Items]
OCI before tax accumulated derivative gain (loss) beginning of period	$ (1)	$ 3	$ 0	$ (5)
OCI before tax accumulated derivative gain (loss) end of period	(1)	8	(1)	8
Commodity Derivative Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
OCI, before Reclassifications, before Tax, Attributable to Parent	0	8	0	12
Commodity Derivative Contracts [Member] \| Cost Of Products Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	0	(3)	(3)	(6)
Foreign Exchange Forward
Derivative Instruments, Gain (Loss) [Line Items]
OCI, before Reclassifications, before Tax, Attributable to Parent	2	1	7	5
Foreign Exchange Forward \| Cost Of Products Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	$ (2)	$ (1)	(6)	1
Interest Rate Contract [Member] \| Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax			$ 1	$ 1

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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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.

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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