Condensed Consolidated Statement Of Shareholders' Equity (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Capital in excess of par value	Retained earnings	Retained earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated other comprehensive loss	Total Walmart shareholders' equity	Total Walmart shareholders' equity Cumulative Effect, Period of Adoption, Adjustment	Noncontrolling interest	Noncontrolling interest Cumulative Effect, Period of Adoption, Adjustment
Beginning balance (in shares) at Jan. 31, 2019			2,878
Beginning balance at Jan. 31, 2019	$ 79,634	$ (300)	$ 288	$ 2,965	$ 80,785	$ (266)	$ (11,542)	$ 72,496	$ (266)	$ 7,138	$ (34)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
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, Value	(2,087)		$ (2)	(73)	(2,012)			(2,087)
Dividends declared to noncontrolling interests	(481)									(481)
Other (in shares)			5
Stockholders' Equity, 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	$ (300)	$ 288	2,965	80,785	$ (266)	(11,542)	72,496	$ (266)	7,138	$ (34)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income	10,907
Other comprehensive income (loss), net of income taxes	$ (915)
Dividends declared per common share (in dollars per share)	$ 2.12
Ending balance (in shares) at Oct. 31, 2019			2,839
Ending balance at Oct. 31, 2019	$ 78,307		$ 284	3,091	80,656		(12,382)	71,649		6,658
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, Value	(1,555)		$ (2)	(54)	(1,499)			(1,555)
Dividends declared to noncontrolling interests	6									6
Stockholders' Equity, 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
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income	3,321				3,288			3,288		33
Other comprehensive income (loss), net of income taxes	$ (1,305)						(1,112)	(1,112)		(193)
Dividends declared per common share (in dollars per share)	$ 0
Dividends declared	$ 5				5			5
Purchase of Company stock (in shares)			(10)
Purchase of Company stock, Value	(1,108)		$ (1)	(39)	(1,068)			(1,108)
Dividends declared to noncontrolling interests	3									3
Other (in shares)			2
Stockholders' Equity, Other	260			250	(1)			249		11
Ending balance (in shares) at Oct. 31, 2019			2,839
Ending balance at Oct. 31, 2019	78,307		$ 284	3,091	80,656		(12,382)	71,649		6,658
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, Value	(693)		$ (1)	(26)	(666)			(693)
Dividends declared to noncontrolling interests	(359)									(359)
Other (in shares)			6
Stockholders' Equity, 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	15,714
Other comprehensive income (loss), net of income taxes	$ (2,362)
Dividends declared per common share (in dollars per share)	$ 2.16
Ending balance (in shares) at Oct. 31, 2020			2,831
Ending balance at Oct. 31, 2020	$ 87,504		$ 283	3,485	92,279		(14,616)	81,431		6,073
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 interests	(3)									(3)
Other (in shares)			2
Stockholders' Equity, 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
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income	5,201				5,135			5,135		66
Other comprehensive income (loss), net of income taxes	$ 1,277						1,168	1,168		109
Dividends declared per common share (in dollars per share)	$ 0
Purchase of Company stock (in shares)			(4)
Purchase of Company stock, Value	$ (486)			(17)	(469)			(486)
Dividends declared to noncontrolling interests	(8)									(8)
Other (in shares)			1
Stockholders' Equity, Other	323			305	(1)			304		19
Ending balance (in shares) at Oct. 31, 2020			2,831
Ending balance at Oct. 31, 2020	$ 87,504		$ 283	$ 3,485	$ 92,279		$ (14,616)	$ 81,431		$ 6,073