Segments and Disaggregated Revenue (Operating Income by Segment, Interest, Net, Loss on extinguishment of debt, and Unrealized (Gains) and Losses) (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 30, 2022	Apr. 30, 2021
Segment Reporting Information [Line Items]
Operating income	$ 5,318	$ 6,909
Interest, net	419	536
Other (gains) and losses	1,998	2,529
Income before income taxes	2,901	3,844
Corporate and support
Segment Reporting Information [Line Items]
Operating income	(376)	(315)
Walmart U.S. \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	4,462	5,455
Walmart International \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	772	1,194
Sam's Club \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	$ 460	$ 575

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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