Summary of Significant Accounting Policies (Schedule of Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 31, 2021	Jan. 31, 2020
Goodwill [Roll Forward]
Goodwill	$ 31,073	$ 31,181
Changes in currency translation and other	10	(149)
Acquisitions	111	41
Amounts reclassified related to operations held for sale	(2,211)
Goodwill	28,983	31,073
Walmart U S [Member]
Goodwill [Roll Forward]
Goodwill	2,593	2,552
Changes in currency translation and other	0	0
Acquisitions	103	41
Amounts reclassified related to operations held for sale	0
Goodwill	2,696	2,593
Walmart International [Member]
Goodwill [Roll Forward]
Goodwill	28,167	28,316
Changes in currency translation and other	10	(149)
Acquisitions	0	0
Amounts reclassified related to operations held for sale	(2,211)
Goodwill	25,966	28,167
Sams Club [Member]
Goodwill [Roll Forward]
Goodwill	313	313
Changes in currency translation and other	0	0
Acquisitions	8	0
Amounts reclassified related to operations held for sale	0
Goodwill	$ 321	$ 313

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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