Goodwill and intangibles - Composition of Finite-Lived Intangibles (Details) - USD ($) $ in Millions	Jul. 31, 2021	Jan. 30, 2021	Aug. 01, 2020
Intangible assets, net:
Gross carrying amount	$ 17.2	$ 5.6	$ 5.6
Accumulated amortization	(5.4)	(4.2)	(3.8)
Net carrying amount	11.8	1.4	1.8
Indefinite-lived intangible assets	177.9	177.6	177.2
Intangible assets, gross	195.1	183.2	182.8
Total intangible assets, net	189.7	179.0	179.0
Intangible liabilities, net
Gross carrying amount	(38.0)	(38.0)	(38.0)
Accumulated amortization	30.0	27.5	24.9
Total	$ (8.0)	$ (10.5)	$ (13.1)

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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