Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Apr. 30, 2023	Jul. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 2
Other Current Assets [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Margin Deposit Assets	$ 24	$ 8
Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Maximum Length of Time, Foreign Currency Cash Flow Hedge	18 months
Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	$ 0	0
Commodity Derivative Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Maximum Length of Time Hedged in Price Risk Cash Flow Hedge	18 months
Commodity Derivative Contracts [Member] \| Maximum [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Term of Contract	18 months
Equity Contracts [Member] \| Maximum [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Term of Contract	12 months
Derivatives Designated As Hedges [Member] \| Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	$ 139	140
Derivatives Designated As Hedges [Member] \| Commodity Derivative Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	0	3
Derivatives Not Designated As Hedges [Member] \| Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	18	13
Derivatives Not Designated As Hedges [Member] \| Commodity Derivative Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	250	254
Derivatives Not Designated As Hedges [Member] \| Embedded Derivative Financial Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	77	39
Derivatives Not Designated As Hedges [Member] \| Equity Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	$ 42	$ 50
Wal-Mart Stores, Inc. [Member] \| Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Concentration Risk, Percentage		22.00%
Top Five Customers [Member] \| Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Concentration Risk, Percentage		47.00%

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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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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Nominal or face amount used to calculate payment on derivative.

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Maximum period of time the entity is hedging its exposure to variability in future cash flows for forecasted transactions, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes forecasted transactions related to payment of variable interest on existing financial instruments.

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Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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