Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Apr. 30, 2021	Jan. 31, 2023	Jan. 31, 2022	Jan. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Losses on disposal of business operations		$ 0	$ 433	$ 8,401
Fair Value, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Losses on disposal of business operations	$ 400
Asda | Disposal Group, Held-for-sale, Not Discontinued Operations
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
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Losses on disposal of business operations				$ 8,300