Amount of cash paid to acquire the entity.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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- Definition

Percentage of voting equity interests acquired in the business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph c
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The amount of acquisition cost of a business combination allocated to assets acquired.

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- Definition

Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB
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The amount of acquisition cost of a business combination allocated to liabilities assumed.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Number 141
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Represents the number of stores.

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Business acquisition purchase price allocation non-controlling interest.

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Number of Countries with Operations

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Acquisitions (Narrative) (Details)		6 Months Ended
Acquisitions (Narrative) (Details)	Jul. 31, 2011 Stores In South Africa [Member] Massmart Holdings Limited [Member]	Jul. 31, 2011 Stores In Sub-Saharan African Countries [Member] Massmart Holdings Limited [Member]	Feb. 28, 2007 Initial Interest [Member] Bounteous Company Limited [Member] USD ($)	Feb. 28, 2007 Additional Consideration [Member] Bounteous Company Limited [Member] USD ($)	Apr. 30, 2011 Netto Food Stores Limited [Member] USD ($)	Apr. 30, 2011 Netto Food Stores Limited [Member] GBP (£)	Jun. 30, 2011 Massmart Holdings Limited [Member] ZAR	Jun. 30, 2011 Massmart Holdings Limited [Member] USD ($)	Feb. 28, 2007 Bounteous Company Limited [Member]
Ownership percentage							51.00%	51.00%	35.00%
Cost of acquisition			$ 264,000,000	$ 376,000,000
Additional percentage of voting interests acquired through share-repurchase program									30.00%
Purchase price					1,200,000,000	750,000,000	16,900,000,000	2,500,000,000
Assets acquired					1,300,000,000			6,400,000,000
Goodwill					748,000,000			3,500,000,000
Liabilities assumed					103,000,000			1,900,000,000
Non-controlling interest								$ 2,000,000,000
Number of stores	290				147	147
Number of countries with operations		13