Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

Reference 2: 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)(2))
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I)
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-Name Accounting Standards Codification
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-Section 50
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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

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Amount of foreign earnings repatriated from subsidiaries outside the country of domicile.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to repatriation of foreign earnings.

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Tax Cuts And Jobs Act Of 2017 Incomplete Accounting Provisional Income Tax Expense Benefit

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Taxes [Line Items]

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Accounting Policies Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
	Jul. 31, 2018	Jul. 31, 2018	Jan. 31, 2019	Jan. 31, 2018
Taxes [Line Items]
Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Provisional Income Tax Expense Benefit	$ 0	$ 123		$ 207
Federal Statutory Income Tax Rate, Percent		21.00%
Effective Income Tax Rate, Percent	283.00%	52.00%
Scenario, Forecast [Member]
Taxes [Line Items]
Foreign Earnings Repatriated			$ 5,000
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			$ 0
Walmart Brazil [Member]
Taxes [Line Items]
Effective Income Tax Rate, Other Adjustments, Percent	227.00%	28.00%
Tax Cuts and Jobs Act [Member]
Taxes [Line Items]
Effective Income Tax Rate, Other Adjustments, Percent	31.00%