Earnings per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Nov. 03, 2012	Oct. 29, 2011	Nov. 03, 2012	Oct. 29, 2011
Numerator
Net earnings (loss) from continuing operations	$ (5)	$ 220	$ 149	$ 661
Net (earnings) loss from continuing operations attributable to noncontrolling interests	(8)	(47)	11	(83)
Net earnings (loss) from continuing operations attributable to Best Buy Co., Inc., basic	(13)	173	160	578
Adjustment for assumed dilution:
Interest on convertible debentures, net of tax (in dollars)	0	1	0	4
Net earnings (loss) attributable to Best Buy Co., Inc., diluted (in dollars)	$ (13)	$ 174	$ 160	$ 582
Denominator
Weighted-average common shares outstanding (in shares)	337.2	363.4	339.3	376.9
Effect of potentially dilutive securities:
Shares from assumed conversion of convertible debentures (in shares)	0	8.8	0	8.8
Stock options and other (in shares)	0	0.2	1.1	0.5
Weighted-average common shares outstanding, assuming dilution (in shares)	337.2	372.4	340.4	386.2
Net earnings (loss) per share from continuing operations attributable to Best Buy Co., Inc.
Basic (in dollars per share)	$ (0.04)	$ 0.48	$ 0.47	$ 1.53
Diluted (in dollars per share)	$ (0.04)	$ 0.47	$ 0.47	$ 1.51
Antidilutive securities excluded from computation of earnings per share	30.7	34.1	28.6	30.2