Segments and Disaggregated Revenue (Revenue, Walmart US) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2022	Oct. 31, 2021	Oct. 31, 2022	Oct. 31, 2021
Revenue from External Customer [Line Items]
Net sales	$ 151,469	$ 139,207	$ 443,138	$ 416,237
Walmart U.S.
Revenue from External Customer [Line Items]
Net sales	104,775	96,609	306,809	287,968
Walmart U.S. | Grocery
Revenue from External Customer [Line Items]
Net sales	63,231	55,560	181,464	161,600
Walmart U.S. | General merchandise
Revenue from External Customer [Line Items]
Net sales	27,605	28,544	85,057	90,858
Walmart U.S. | Health and wellness
Revenue from External Customer [Line Items]
Net sales	11,947	11,030	34,172	31,480
Walmart U.S. | Other categories
Revenue from External Customer [Line Items]
Net sales	$ 1,992	$ 1,475	$ 6,116	$ 4,030