Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Jan. 28, 2017	Mar. 20, 2017	Jul. 29, 2016
Document and Entity Information [Abstract}
Entity Registrant Name	BEST BUY CO INC
Current Fiscal Year End Date	--01-28
Entity Voluntary Filers	No
Document Fiscal Year Focus	2017
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Well-known Seasoned Issuer	Yes
Entity Common Stock, Shares Outstanding		309,110,840
Entity Public Float			$ 7.8
Document Fiscal Period Focus	FY
Document Type	10-K
Entity Central Index Key	0000764478
Document Period End Date	Jan. 28, 2017
Entity Filer Category	Large Accelerated Filer