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Goodwill and intangibles - Summary of Goodwill (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	May 02, 2020	Aug. 03, 2019	Jan. 30, 2021	Feb. 01, 2020	Feb. 02, 2019
Goodwill [Roll Forward]
Beginning balance	$ 248.8		$ 248.8
Impairment			(10.7)	$ (47.7)	$ (521.2)
Ending balance			238.0	248.8
North America
Goodwill [Roll Forward]
Beginning balance	248.8		248.8	296.6
Impairment	$ (10.7)	$ (47.7)	(10.7)	(47.7)	(308.8)
Impact of foreign exchange			(0.1)	(0.1)
Ending balance			$ 238.0	$ 248.8	296.6
R2Net Inc. \| North America
Goodwill [Roll Forward]
Impairment		$ (12.5)			$ (208.8)