Other operating income (loss) - Components of Other Operating Income, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 30, 2021	Feb. 01, 2020	Feb. 02, 2019
Other Income and Expenses [Abstract]
Interest income from in-house customer finance programs	$ 4.2	$ 0.0	$ 22.8
Shareholder litigation charge, net of insurance recoveries	(7.5)	(33.2)	0.0
De-designated cash flow hedges	9.9	0.0	0.0
Other	(4.2)	3.6	3.4
Other operating income (loss)	$ 2.4	$ (29.6)	$ 26.2