Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2015	Nov. 01, 2014	Oct. 31, 2015	Nov. 01, 2014
Numerator
Net earnings from continuing operations attributable to Best Buy Co., Inc.	$ 129	$ 116	$ 330	$ 722
Denominator
Weighted-average common shares outstanding (in shares)	344.7	350.1	348.9	349.0
Effect of potentially dilutive securities:
Nonvested share awards (in shares)	4.3	3.9	4.7	3.5
Weighted-average common shares outstanding, assuming dilution (in shares)	349.0	354.0	353.6	352.5
Net earnings per share from continuing operations attributable to Best Buy Co., Inc.
Basic (in dollars per share)	$ 0.37	$ 0.33	$ 0.95	$ 2.07
Diluted (in dollars per share)	$ 0.37	$ 0.33	$ 0.93	$ 2.04
Antidilutive securities excluded from computation of earnings per share	10.1	11.6	10.0	13.8