Segments and Disaggregated Revenue (Operating Income by Segment, Interest and Other (Gains) and Losses) (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 30, 2023	Apr. 30, 2022
Segment Reporting Information [Line Items]
Operating income	$ 6,240	$ 5,318
Interest, net	557	419
Other (gains) and losses	2,995	1,998
Income before income taxes	2,688	2,901
Corporate and support
Segment Reporting Information [Line Items]
Operating income	(366)	(376)
Walmart U.S. \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	4,984	4,462
Walmart International \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	1,164	772
Sam's Club \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	$ 458	$ 460

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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