Net Income Per Common Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2013	Oct. 31, 2012
Net Income Per Common Share [Line Items]
Income from continuing operations	$ 3,870	$ 3,809	$ 12,007	$ 11,841
Income (Loss) from Continuing Operations Attributable to Noncontrolling Interest	(143)	(185)	(443)	(475)
Income (Loss) from Continuing Operations Attributable to Parent	$ 3,727	$ 3,624	$ 11,564	$ 11,366
Weighted-average common shares outstanding, basic	3,257	3,364	3,279	3,385
Dilutive impact of stock options and other share-based awards	14	15	14	15
Weighted-average common shares outstanding, diluted	3,271	3,379	3,293	3,400
Basic income per common share from continuing operations attributable to Walmart	$ 1.14	$ 1.08	$ 3.53	$ 3.36
Diluted income per common share from continuing operations attributable to Walmart	$ 1.14	$ 1.07	$ 3.51	$ 3.34