Quarterly Financial Information - Unaudited (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Feb. 02, 2019	Nov. 03, 2018	Aug. 04, 2018	May 05, 2018	Feb. 03, 2018	Oct. 28, 2017	Jul. 29, 2017	Apr. 29, 2017	Feb. 02, 2019	Feb. 03, 2018	Jan. 28, 2017
Quarterly Financial Information Disclosure [Abstract]
Sales	$ 2,154.7	$ 1,191.7	$ 1,420.1	$ 1,480.6	$ 2,293.1	$ 1,156.9	$ 1,399.6	$ 1,403.4	$ 6,247.1	$ 6,253.0	$ 6,408.4
Gross margin	877.8	371.2	427.0	484.8	919.8	321.1	457.9	491.2	2,160.8	2,190.0	2,360.8
Net income	$ (116.2)	$ (38.1)	$ (31.2)	$ (504.8)	$ 343.0	$ (12.1)	$ 85.2	$ 70.3	$ (657.4)	$ 519.3	$ 543.2
Earnings (loss) per common share:
Earnings per share - basic (usd per share)	$ (2.25)	$ (0.74)	$ (0.56)	$ (8.48)	$ 5.70	$ (0.20)	$ 1.34	$ 1.03	$ (12.62)	$ 7.72	$ 7.13
Earnings per share - diluted (usd per share)	$ (2.25)	$ (0.74)	$ (0.56)	$ (8.48)	$ 5.24	$ (0.20)	$ 1.33	$ 1.03	$ (12.62)	$ 7.44	$ 7.08