Comprehensive Income (Unaudited) (Parenthetical) (USD $) In Millions	3 Months Ended
Apr. 30, 2011	Apr. 30, 2010
Comprehensive Income
Consolidated net income, redeemable noncontrolling interest	$ 17	$ 3
Foreign currency translation, redeemable noncontrolling interest	$ (17)	$ 26

Name:

wmt_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToRedeemableNoncontrollingInterest

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wmt

Data Type:

xbrli:monetaryItemType

Balance Type:

debit

Period Type:

duration