Earnings per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
May 02, 2015	May 03, 2014
Numerator
Net earnings from continuing operations	$ 37	$ 469
Net earnings from continuing operations attributable to Best Buy Co., Inc.	$ 37	$ 469
Denominator
Weighted-average common shares outstanding (in shares)	352.4	347.4
Effect of potentially dilutive securities:
Nonvested share awards (in shares)	5.2	3.0
Weighted-average common shares outstanding, assuming dilution (in shares)	357.6	350.4
Net earnings per share from continuing operations attributable to Best Buy Co., Inc.
Basic (in dollars per share)	$ 0.11	$ 1.35
Diluted (in dollars per share)	$ 0.10	$ 1.33
Antidilutive securities excluded from computation of earnings per share	10.1	16.2

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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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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest.

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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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The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units 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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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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