Document Information Statement - shares	6 Months Ended
Aug. 04, 2018	Sep. 05, 2018
Document Information [Abstract]
Entity Common Stock, Shares Outstanding		274,557,555
Entity Registrant Name	BEST BUY CO INC
Entity Central Index Key	0000764478
Document Type	10-Q
Document Period End Date	Aug. 04, 2018
Amendment Flag	false
Current Fiscal Year End Date	--02-02
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2

Document Information [Abstract]

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This is focus fiscal period of the document report. For a first quarter 2006 quarterly report, which may also provide financial information from prior periods, the first fiscal quarter should be given as the fiscal period focus. Values: FY, Q1, Q2, Q3, Q4, H1, H2, M9, T1, T2, T3, M8, CY.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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