Shareholders' Equity Components of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Feb. 03, 2018	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Foreign currency translation	$ 314	$ 279	$ 271	$ 382
Total Best Buy Co., Inc. Shareholders' Equity
Accumulated Other Comprehensive Income (Loss) [Line Items]
Foreign currency translation adjustments	$ 35	10	(44)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification of (gains) losses on available-for-sale investments into earnings		$ 2	$ 67