Restructuring Charges Composition of Restructuring Charges (Details) - USD ($) $ in Millions	3 Months Ended
	May 05, 2018	Apr. 29, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 30	$ 0
Restructuring Program Best Buy Mobile [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	30
Restructuring and Related Cost, Cost Incurred to Date	39
Restructuring Program Best Buy Mobile [Member] | Property and equipment write-downs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0
Restructuring and Related Cost, Cost Incurred to Date	1
Restructuring Program Best Buy Mobile [Member] | Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1
Restructuring and Related Cost, Cost Incurred to Date	9
Restructuring Program Best Buy Mobile [Member] | Facility closure and other costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	29
Restructuring and Related Cost, Cost Incurred to Date	$ 29