Earnings per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Nov. 01, 2014	Nov. 02, 2013	Nov. 01, 2014	Nov. 02, 2013
Numerator
Net earnings from continuing operations	$ 107	$ 44	$ 714	$ 378
Net earnings from continuing operations attributable to noncontrolling interests	0	(1)	(1)	(1)
Net earnings from continuing operations attributable to Best Buy Co., Inc.	$ 107	$ 43	$ 713	$ 377
Denominator
Weighted-average common shares outstanding (in shares)	350.1	342.8	349.0	340.7
Effect of potentially dilutive securities:
Nonvested share awards (in shares)	3.9	6.1	3.5	4.6
Weighted-average common shares outstanding, assuming dilution (in shares)	354.0	348.9	352.5	345.3
Net earnings per share from continuing operations attributable to Best Buy Co., Inc.
Basic (in dollars per share)	$ 0.30	$ 0.13	$ 2.05	$ 1.11
Diluted (in dollars per share)	$ 0.30	$ 0.12	$ 2.02	$ 1.09
Antidilutive securities excluded from computation of earnings per share	11.6	12.6	13.8	16.4

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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Amount of income (loss) from continuing operations attributable to the noncontrolling interest. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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