Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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-Name Regulation S-X (SX)
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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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A disclosure of an assertion that the amount of cash flow hedge ineffectiveness is immaterial.

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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.

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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.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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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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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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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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Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended	12 Months Ended
	Apr. 29, 2018	Oct. 29, 2017	Apr. 29, 2018	Jul. 29, 2018	Jul. 30, 2017	Jul. 31, 2016	Mar. 13, 2018	Oct. 16, 2017
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net				$ 24	$ 0	$ (1)
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months				$ 1
Cash Flow Hedge Ineffectiveness is Immaterial				The ineffective portion and amount excluded from effectiveness testing were not material.
Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Margin Deposit Assets				$ 2	1
Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Contracts Mature Within, Months				18 months
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net				$ 8	(4)	(9)
Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net				$ 15	23	$ (36)
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	$ 15	$ (22)	$ (7)
Commodity Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Maximum Length of Contract Maturity				18 months
Deferred Compensation Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Maximum Length of Contract Maturity				12 months
Derivatives Designated As Hedges [Member] \| Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount				$ 104	84
Derivatives Designated As Hedges [Member] \| Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount					300		$ 300	$ 300
Derivatives Designated As Hedges [Member] \| Commodity Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount				0	0
Derivatives Not Designated As Hedges [Member] \| Treasury Lock [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount							$ 2,400
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ 18
Derivatives Not Designated As Hedges [Member] \| Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount				140	336
Derivatives Not Designated As Hedges [Member] \| Currency Swap [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount				0	0
Derivatives Not Designated As Hedges [Member] \| Commodity Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount				118	90
Derivatives Not Designated As Hedges [Member] \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount				33	35
Derivatives Not Designated As Hedges [Member] \| Deferred Compensation Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount				$ 41	$ 43
Wal-Mart Stores, Inc. [Member] \| Customer Concentration Risk [Member] \| Sales Revenue, Net [Member]
Derivatives, Fair Value [Line Items]
Entity Wide Revenue, Major Customer, Percentage Of Net Sales				18.00%	20.00%	20.00%
Top Five Customers [Member] \| Customer Concentration Risk [Member] \| Sales Revenue, Net [Member]
Derivatives, Fair Value [Line Items]
Entity Wide Revenue, Major Customer, Percentage Of Net Sales				38.00%