Condensed Consolidated Statements Of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2012	Oct. 31, 2011
Statement of Other Comprehensive Income [Abstract]
Consolidated net income	$ 3,825	$ 3,493	$ 11,880	$ 10,980
Less consolidated net income attributable to noncontrolling interest	(176)	(146)	(448)	(404)
Less consolidated net income attributable to redeemable noncontrolling interest	(14)	(11)	(39)	(40)
Consolidated net income attributable to Walmart	3,635	3,336	11,393	10,536
Other comprehensive income, net of income taxes
Currency translation and other	876	(3,546)	1,232	(2,646)
Derivatives instruments	250	15	(135)	(98)
Minimum pension liabilities	(1)	0	3	0
Other comprehensive income, net of income taxes	1,125	(3,531)	1,100	(2,744)
Less other comprehensive income attributable to noncontrolling interest	(122)	806	(196)	663
Less other comprehensive income attributable to redeemable noncontrolling interest	(34)	64	(56)	60
Other comprehensive income attributable to Walmart	969	(2,661)	848	(2,021)
Comprehensive income, net of income taxes	4,950	(38)	12,980	8,236
Less comprehensive income attributable to noncontrolling interest	(298)	660	(644)	259
Less comprehensive income attributable to redeemable noncontrolling interest	(48)	53	(95)	20
Comprehensive income attributable to Walmart	$ 4,604	$ 675	$ 12,241	$ 8,515