Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Losses on disposal of business operations	$ 433	$ 8,401	$ 15
Asda [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Losses on disposal of business operations		5,500
Accumulated pension components included in disposal group, expected amount		2,300
Walmart International [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Losses on disposal of business operations	$ 400	$ 8,300
Impairment charges			400
Walmart U S [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges			$ 500