Segments (Reconciliation of Revenue from Segments to Consolidated) (Details) (USD $) In Millions	3 Months Ended
Apr. 30, 2011	Apr. 30, 2010
Net sales	$ 103,415	$ 99,097
Walmart U.S. [Member]
Net sales	62,669	62,324
Walmart International [Member]
Net sales	27,905	25,030
Sam's Club [Member]
Net sales	$ 12,841	$ 11,743

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 1
-Article 5

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration