Condensed Consolidated Statement Of Shareholders' Equity (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Capital in excess of par value	Retained earnings	Accumulated other comprehensive loss	Total Walmart shareholders' equity	Noncontrolling interest
Beginning balance (in shares) at Jan. 31, 2019		2,878
Beginning balance at Jan. 31, 2019	$ 79,634	$ 288	$ 2,965	$ 80,785	$ (11,542)	$ 72,496	$ 7,138
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of new accounting standards on February 1, 2019, net of income taxes	(300)			(266)		(266)	(34)
Consolidated net income	3,906			3,842		3,842	64
Other comprehensive income (loss), net of income taxes	485				451	451	34
Dividends declared	(6,071)			(6,071)		(6,071)
Purchase of Company stock (in shares)		(21)
Purchase of Company stock	(2,087)	$ (2)	(73)	(2,012)		(2,087)
Dividends declared to noncontrolling interest	(481)						(481)
Other (in shares)		5
Other	(176)		(158)	(2)		(160)	(16)
Ending balance (in shares) at Apr. 30, 2019		2,862
Ending balance at Apr. 30, 2019	74,910	$ 286	2,734	76,276	(11,091)	68,205	6,705
Beginning balance (in shares) at Jan. 31, 2019		2,878
Beginning balance at Jan. 31, 2019	79,634	$ 288	2,965	80,785	(11,542)	72,496	7,138
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income	7,586
Other comprehensive income (loss), net of income taxes	390
Ending balance (in shares) at Jul. 31, 2019		2,847
Ending balance at Jul. 31, 2019	77,131	$ 285	2,880	78,432	(11,270)	70,327	6,804
Beginning balance (in shares) at Apr. 30, 2019		2,862
Beginning balance at Apr. 30, 2019	74,910	$ 286	2,734	76,276	(11,091)	68,205	6,705
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income	3,680			3,610		3,610	70
Other comprehensive income (loss), net of income taxes	(95)				(179)	(179)	84
Dividends declared	15			15		15
Purchase of Company stock (in shares)		(15)
Purchase of Company stock	(1,555)	$ (2)	(54)	(1,499)		(1,555)
Dividends declared to noncontrolling interest	6						6
Other	170	$ 1	200	30		231	(61)
Ending balance (in shares) at Jul. 31, 2019		2,847
Ending balance at Jul. 31, 2019	77,131	$ 285	2,880	78,432	(11,270)	70,327	6,804
Beginning balance (in shares) at Jan. 31, 2020		2,832
Beginning balance at Jan. 31, 2020	81,552	$ 284	3,247	83,943	(12,805)	74,669	6,883
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income	4,074			3,990		3,990	84
Other comprehensive income (loss), net of income taxes	(4,075)				(3,363)	(3,363)	(712)
Dividends declared	(6,117)			(6,117)		(6,117)
Purchase of Company stock (in shares)		(6)
Purchase of Company stock	(693)	$ (1)	(26)	(666)		(693)
Dividends declared to noncontrolling interest	(359)						(359)
Other (in shares)		6
Other	(272)	$ 1	(238)	(9)		(246)	(26)
Ending balance (in shares) at Apr. 30, 2020		2,832
Ending balance at Apr. 30, 2020	74,110	$ 284	2,983	81,141	(16,168)	68,240	5,870
Beginning balance (in shares) at Jan. 31, 2020		2,832
Beginning balance at Jan. 31, 2020	81,552	$ 284	3,247	83,943	(12,805)	74,669	6,883
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income	10,513
Other comprehensive income (loss), net of income taxes	(3,639)
Ending balance (in shares) at Jul. 31, 2020		2,834
Ending balance at Jul. 31, 2020	81,197	$ 283	3,197	87,614	(15,784)	75,310	5,887
Beginning balance (in shares) at Apr. 30, 2020		2,832
Beginning balance at Apr. 30, 2020	74,110	$ 284	2,983	81,141	(16,168)	68,240	5,870
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income	6,439			6,476		6,476	(37)
Other comprehensive income (loss), net of income taxes	436				384	384	52
Dividends declared to noncontrolling interest	(3)						(3)
Other (in shares)		2
Other	215	$ (1)	214	(3)		210	5
Ending balance (in shares) at Jul. 31, 2020		2,834
Ending balance at Jul. 31, 2020	$ 81,197	$ 283	$ 3,197	$ 87,614	$ (15,784)	$ 75,310	$ 5,887