Segment information - Summary of Activity by Segment (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended		12 Months Ended
	Oct. 31, 2020	May 02, 2020	Nov. 02, 2019	Aug. 03, 2019	Oct. 31, 2020	Nov. 02, 2019	Feb. 01, 2020
Segment Reporting Information [Line Items]
Sales	$ 1,300.3		$ 1,187.7		$ 3,040.4	$ 3,983.8
Operating income (loss)	39.7		(39.9)		(349.6)	(64.9)
Interest expense, net	(9.1)		(8.6)		(25.6)	(27.9)
Other non-operating income, net	0.0		7.0		0.3	7.5
Income (loss) before income taxes	30.6		(41.5)		(374.9)	(85.3)
Restructuring charge (benefit)	2.0		1.4		1.4	5.8
Asset impairments	1.5		0.0		158.1	47.7
Goodwill impairment	0.0		0.0	$ 47.7	10.7	47.7
North America
Segment Reporting Information [Line Items]
Sales	1,182.7		1,070.7		2,786.8	3,612.0
Goodwill impairment		$ 10.7			10.7		$ 47.7
International
Segment Reporting Information [Line Items]
Sales	106.9		106.4		232.8	331.8
Other
Segment Reporting Information [Line Items]
Sales	10.7		10.6		20.8	40.0
Reportable segments | North America
Segment Reporting Information [Line Items]
Sales	1,182.7		1,070.7		2,786.8	3,612.0
Operating income (loss)	52.9		(10.7)		(238.3)	29.4
Restructuring charge (benefit)	2.2		1.4		1.6	2.6
Severance costs	0.7		5.5		37.3	37.7
Asset impairments	1.5				136.9
Goodwill impairment						47.7
Reportable segments | International
Segment Reporting Information [Line Items]
Sales	106.9		106.4		232.8	331.8
Operating income (loss)	1.6		(5.9)		(52.6)	(16.5)
Severance costs	3.0		0.8		7.6	2.4
Asset impairments					21.2
Reportable segments | Other
Segment Reporting Information [Line Items]
Sales	10.7		10.6		20.8	40.0
Operating income (loss)	1.3		(1.5)		0.8	(14.4)
Restructuring charge (benefit)	(0.2)				(0.2)	3.2
Corporate and unallocated expenses
Segment Reporting Information [Line Items]
Operating income (loss)	(16.1)		(21.8)		(59.5)	(63.4)
Severance costs			$ 2.9		0.3	$ 19.3
Gain (loss) related to litigation settlement					$ (7.5)
Restructuring credits	$ 0.1