Amount of cash paid to acquire the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph f(1)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d

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- Definition

Percentage of voting equity interests acquired in the business combination.

+ References

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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 18
-Subparagraph f

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 20
-Subparagraph a (1)

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- Definition

Number of Countries with Operations

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- Definition

Number of stores operated by entity

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- Definition

Stores Acquired from Entity

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Acquisitions (Narrative) (Details) In Millions, unless otherwise specified		3 Months Ended
	Apr. 30, 2011 Stores in South Africa [Member] Massmart Holdings Ltd [Member]	Apr. 30, 2011 Stores in Sub-Saharan African Countries [Member] Massmart Holdings Ltd [Member]	Feb. 28, 2007 Initial Interest [Member] Bounteous Company Limited [Member] USD ($)	Feb. 28, 2007 Additional Consideration [Member] Bounteous Company Limited [Member] USD ($)	Feb. 28, 2007 Bounteous Company Limited [Member]	Apr. 30, 2011 Netto Food Stores Limited [Member] USD ($)	Apr. 30, 2011 Netto Food Stores Limited [Member] GBP (£)	Nov. 29, 2010 Massmart Holdings Ltd [Member] ZAR	Nov. 29, 2010 Massmart Holdings Ltd [Member] USD ($)
Ownership percentage					35.00%			51.00%	51.00%
Cost of acquisition			$ 264	$ 376
Additional percentage of voting interests acquired through share-repurchase program					30.00%
Stores acquired from entity						147	147
Estimated purchase price for shares						$ 1,300	£ 778	17,000	$ 2,300
Number of stores operated by entity	290
Number of countries with operations		13