Net Income Per Common Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Apr. 30, 2014	Apr. 30, 2013
Net Income Per Common Share [Line Items]
Income from continuing operations	$ 3,711	$ 3,932
Less income from continuing operations attributable to noncontrolling interest	(129)	(157)
Income from continuing operations attributable to Walmart	$ 3,582	$ 3,775
Weighted-average common shares outstanding, basic	3,233	3,301
Dilutive impact of stock options and other share-based awards	15	17
Weighted-average common shares outstanding, diluted	3,248	3,318
Basic income per common share from continuing operations attributable to Walmart	$ 1.10	$ 1.14
Diluted income per common share from continuing operations attributable to Walmart	$ 1.10	$ 1.14

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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Amount of income (loss) from continuing operations attributable to the noncontrolling interest. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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