Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended
Jan. 29, 2017	Jul. 31, 2016
Derivatives, Fair Value [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 8
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	$ 1	$ 5
Currency Swap [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	0	0
Derivatives Designated As Hedges [Member] \| Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	71	91
Derivatives Designated As Hedges [Member] \| Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	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] \| Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	118	175
Derivatives Not Designated As Hedges [Member] \| Commodity Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	58	88
Derivatives Not Designated As Hedges [Member] \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	75
Derivatives Not Designated As Hedges [Member] \| Deferred Compensation Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 45	$ 44
Maximum [Member] \| Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative, Term of Contract	18 months
Maximum [Member] \| Commodity Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Term of Contract	18 months
Maximum [Member] \| Deferred Compensation Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Term of Contract	12 months
Wal-Mart Stores, Inc. [Member] \| Customer Concentration Risk [Member]
Derivatives, Fair Value [Line Items]
Entity Wide Revenue, Major Customer, Percentage Of Net Sales	20.00%
Top Five Customers [Member] \| Customer Concentration Risk [Member]
Derivatives, Fair Value [Line Items]
Entity Wide Revenue, Major Customer, Percentage Of Net Sales	40.00%

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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- Definition

A disclosure of an assertion that the amount of cash flow hedge ineffectiveness is immaterial.

+ 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 (d)(1)
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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Section 50
-Paragraph 21
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- Definition

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

+ References

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.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8,17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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