Segment and Geographic Information Segment Information (Details) $ in Millions		3 Months Ended																12 Months Ended
		Feb. 03, 2018 USD ($)		Oct. 28, 2017 USD ($)		Jul. 29, 2017 USD ($)		Apr. 29, 2017 USD ($)		Jan. 28, 2017 USD ($)		Oct. 29, 2016 USD ($)		Jul. 30, 2016 USD ($)		Apr. 30, 2016 USD ($)		Feb. 03, 2018 USD ($) segments		Jan. 28, 2017 USD ($)		Jan. 30, 2016 USD ($)
Business segment information
Number of reportable segments | segments																		2
Total revenue		$ 15,363		$ 9,320		$ 8,940		$ 8,528		$ 13,482		$ 8,945		$ 8,533		$ 8,443		$ 42,151		$ 39,403		$ 39,528
Operating income(2)		872	[1]	$ 350	[1]	$ 321	[1]	$ 300	[1]	881	[2]	$ 312	[2]	$ 289	[2]	$ 372	[2]	1,843	[1]	1,854	[2]	1,375
Other income (expense)
Gain on sale of investments																		1		3		2
Investment income and other																		48		31		13
Interest expense																		(75)		(72)		(80)
Earnings from continuing operations before income tax expense																		1,817		1,816		1,310
Total assets		13,049								13,856								13,049		13,856		13,519
Total capital expenditures																		688		580		649
Total depreciation																		683		654		657
International Segment [Member]
Business segment information
Total revenue																		$ 3,489		$ 3,155		$ 3,163
Percentage of revenue, by revenue category (as a percent)																		100.00%		100.00%		100.00%
Operating income(2)																		$ 91		$ 90		$ (210)
Other income (expense)
Total assets		1,496								1,360								1,496		1,360		1,201
Total capital expenditures																		82		56		47
Total depreciation																		$ 52		$ 41		$ 44
International Segment [Member] | Consumer Electronics [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		32.00%		31.00%		31.00%
International Segment [Member] | Computing and Mobile Phones [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		46.00%		48.00%		48.00%
International Segment [Member] | Entertainment [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		7.00%		7.00%		9.00%
International Segment [Member] | Appliances [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		8.00%		6.00%		5.00%
International Segment [Member] | Services [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		5.00%		7.00%		6.00%
International Segment [Member] | Other [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		2.00%		1.00%		1.00%
Domestic Segment [Member]
Business segment information
Total revenue																		$ 38,662		$ 36,248		$ 36,365
Percentage of revenue, by revenue category (as a percent)																		100.00%		100.00%		100.00%
Operating income(2)	[3]																	$ 1,752		$ 1,764		$ 1,585
Other income (expense)
Total assets		$ 11,553								$ 12,496								11,553		12,496		12,318
Total capital expenditures																		606		524		602
Total depreciation																		$ 631		$ 613		$ 613
Domestic Segment [Member] | Consumer Electronics [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		33.00%		34.00%		32.00%
Domestic Segment [Member] | Computing and Mobile Phones [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		45.00%		45.00%		46.00%
Domestic Segment [Member] | Entertainment [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		8.00%		7.00%		8.00%
Domestic Segment [Member] | Appliances [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		10.00%		9.00%		8.00%
Domestic Segment [Member] | Services [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		4.00%		5.00%		5.00%
Domestic Segment [Member] | Other [Member]
Business segment information
Percentage of revenue, by revenue category (as a percent)																		0.00%		0.00%		1.00%

[1] Includes $0 million, $2 million, $(2) million and $10 million of restructuring charges (benefit) recorded in the fiscal first, second, third and fourth quarters, respectively, and $10 million for the 12 months ended February 3, 2018, related to measures we took to restructure our businesses. Also includes $80 million related to a one-time bonus for certain employees and $20 million related to a one-time contribution to the Best Buy Foundation in response to future tax savings created by the Tax Act for the fiscal fourth quarter and 12 months ended February 3, 2018.

[2] Includes $29 million, $0 million, $1 million and $9 million of restructuring charges recorded in the fiscal first, second, third and fourth quarters, respectively, and $39 million for the 12 months ended January 28, 2017, related to measures we took to restructure our businesses. Also, includes $161 million of CRT litigation settlements, net of related legal fees and costs, recorded in the fiscal first quarter and in the 12 months ended January 28, 2017, related to products purchased and sold in prior fiscal years.

[3] (1)The Domestic segment operating income includes certain operations that are based in foreign tax jurisdictions and primarily relate to sourcing products into the U.S.