Shareholders' Equity (Details 2) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended		3 Months Ended								12 Months Ended
	Jun. 30, 2011	Jun. 30, 2007	Mar. 03, 2012	Nov. 26, 2011	Aug. 27, 2011	May 28, 2011	Feb. 26, 2011	Nov. 27, 2010	Aug. 28, 2010	May 29, 2010	Mar. 03, 2012	Feb. 26, 2011	Feb. 27, 2010
Outstanding Options to Purchase Common Stock [Line Items]
Exercisable stock options (in shares)			24,403,000								24,403,000
Percentage of exercisable stock options (as a percent)			100.00%								100.00%
Exercisable stock options, weighted-average price (in dollars per share)			$ 40.21								$ 40.21
Unexercisable stock options (in shares)			11,400,000								11,400,000
Percentage of unexercisable stock options (as a percent)			100.00%								100.00%
Unexercisable stock options, weighted-average price (in dollars per share)			$ 27.30								$ 27.30
Total outstanding stock options (in shares)			35,801,000				35,587,000				35,801,000	35,587,000
Percentage of outstanding stock options (as a percent)			100.00%								100.00%
Outstanding stock options, weighted-average price (in dollars per share)			$ 38.08				$ 38.97				$ 38.08	$ 38.97
Numerator [Abstract]
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest			$ (324)	$ 258	$ 197	$ 199	$ 792	$ 280	$ 274	$ 208	$ 330	$ 1,554	$ 1,495
Net (earnings) from continuing operations attributable to noncontrolling interests											(1,387)	(127)	(96)
Net (loss) earnings from continuing operations attributable to Best Buy Co., Inc., basic											(1,057)	1,427	1,399
Adjustment for assumed dilution:
Interest on convertible debentures due in 2022, net of tax											0	6	6
Net earnings from continuing operations attributable to Best Buy Co., Inc., diluted											(1,057)	1,433	1,405
Denominator [Abstract]
Weighted-average common shares outstanding (in shares)											366,300,000	406,100,000	416,800,000
Effect of Potentially Dilutive Securities [Abstract]
Shares from assumed conversion of convertible debentures (in shares)											0	8,800,000	8,800,000
Stock options and other (in shares)											0	1,600,000	1,900,000
Weighted-average common shares outstanding, assuming dilution (in shares)											366,300,000	416,500,000	427,500,000
Earnings per share attributable to Best Buy Co., Inc.
Basic (in dollars per share)											$ (2.89)	$ 3.51	$ 3.36
Diluted (in dollars per share)			$ (4.73)	$ 0.62	$ 0.52	$ 0.41	$ 1.84	$ 0.61	$ 0.62	$ 0.41	$ (2.89)	$ 3.44	$ 3.29
Share repurchases authorized (in shares)	5,000	5,500
Open Market Repurchases [Abstract]
Comprehensive Income (Loss) (in dollars)											(1,314)	1,410	1,674
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign currency translation			93				102				93	102
Unrealized gains (losses) on available-for-sale investments			(3)				72				(3)	72
Unrealized losses on derivative instruments (cash flow hedges)			0				(1)				0	(1)
Total			90				173				90	173
In-the-money [Member]
Outstanding Options to Purchase Common Stock [Line Items]
Exercisable stock options (in shares)			3,600,000								3,600,000
Percentage of exercisable stock options (as a percent)			15.00%								15.00%
Exercisable stock options, weighted-average price (in dollars per share)			$ 25.28								$ 25.28
Unexercisable stock options (in shares)			2,800,000								2,800,000
Percentage of unexercisable stock options (as a percent)			25.00%								25.00%
Unexercisable stock options, weighted-average price (in dollars per share)			$ 25.07								$ 25.07
Total outstanding stock options (in shares)			6,400,000								6,400,000
Percentage of outstanding stock options (as a percent)			18.00%								18.00%
Outstanding stock options, weighted-average price (in dollars per share)			$ 25.19								$ 25.19
Out-of-the-money [Member]
Outstanding Options to Purchase Common Stock [Line Items]
Exercisable stock options (in shares)			20,800,000								20,800,000
Percentage of exercisable stock options (as a percent)			85.00%								85.00%
Exercisable stock options, weighted-average price (in dollars per share)			$ 42.81								$ 42.81
Unexercisable stock options (in shares)			8,600,000								8,600,000
Percentage of unexercisable stock options (as a percent)			75.00%								75.00%
Unexercisable stock options, weighted-average price (in dollars per share)			$ 36.30								$ 36.30
Total outstanding stock options (in shares)			29,400,000								29,400,000
Percentage of outstanding stock options (as a percent)			82.00%								82.00%
Outstanding stock options, weighted-average price (in dollars per share)			$ 40.91								$ 40.91
June 2011 share repurchase program [Member}
Outstanding Options to Purchase Common Stock [Line Items]
Amounting remaining for additional share repurchases											4,111
Open Market Repurchases [Abstract]
Total number of shares repurchased											34,500,000	0	0
Total cost of shares repurchased											889	0	0
June 2007 share repurchase program [Member]
Open Market Repurchases [Abstract]
Total number of shares repurchased											20,100,000	32,600,000	0
Total cost of shares repurchased											$ 611	$ 1,193	$ 0