Discontinued Operations (Details 2) - USD ($) $ in Millions		3 Months Ended								12 Months Ended
		Jan. 28, 2017	Oct. 29, 2016	Jul. 30, 2016	Apr. 30, 2016	Jan. 30, 2016	Oct. 31, 2015	Aug. 01, 2015	May 02, 2015	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax										$ 16
Revenue										0	$ 217	$ 1,564
Restructuring charges	[1]									0	1	18
Gain (loss) from discontinued operations before income tax benefit										28	(8)	(12)
Income tax expense										(7)	(1)	0
Gain on sale of discontinued operations										0	99	1
Net gain (loss) from discontinued operations including noncontrolling interests		$ 0	$ 2	$ 16	$ 3	$ 2	$ (4)	$ 0	$ 92	21	90	(11)
Net (earnings) loss from discontinued operations attributable to noncontrolling interests										0	0	(2)
Net gain (loss) from discontinued operations attributable to Best Buy Co., Inc.										21	90	$ (13)
Derivative, Notional Amount		$ 998				$ 1,052				$ 998	$ 1,052

[1] See Note 4, Restructuring Charges, for further discussion of the restructuring charges associated with discontinued operations.