Restructuring Charges Composition of Restructuring Charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Nov. 03, 2018	Oct. 28, 2017	Nov. 03, 2018	Oct. 28, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0	$ (2)	$ 47	$ 0
Best Buy Mobile
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0	$ 0	47	$ 0
Restructuring and Related Cost, Cost Incurred to Date	56		56
Best Buy Mobile | Property and equipment impairments
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0		0
Restructuring and Related Cost, Cost Incurred to Date	1		1
Best Buy Mobile | Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0		2
Restructuring and Related Cost, Cost Incurred to Date	6		6
Best Buy Mobile | Facility closure and other costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0		49
Restructuring and Related Cost, Cost Incurred to Date	$ 49		$ 49