Segment Operating Income, Income Expense, Net and Income from Continuing Operations before Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 30, 2016	Apr. 30, 2015
Segment Reporting Information [Line Items]
Operating income (loss):	$ 5,275	$ 5,680
Interest, net	561	824
Income from continuing operations before income taxes	4,714	4,856
Walmart U.S.
Segment Reporting Information [Line Items]
Operating income (loss):	4,232	4,639
Walmart International
Segment Reporting Information [Line Items]
Operating income (loss):	1,164	1,070
Sam's Club
Segment Reporting Information [Line Items]
Operating income (loss):	413	427
Corporate and support
Segment Reporting Information [Line Items]
Operating income (loss):	$ (534)	$ (456)

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The net amount of operating interest income (expense).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.10)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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