Goodwill and intangibles - Composition of Finite-Lived Intangibles (Details) - USD ($) $ in Millions	Oct. 31, 2020	Feb. 01, 2020	Nov. 02, 2019
Intangible assets, net:
Gross carrying amount	$ 53.1	$ 53.2	$ 53.2
Accumulated amortization	(51.5)	(50.9)	(50.7)
Net carrying amount	1.6	2.3	2.5
Indefinite-lived intangible assets, gross	474.7	475.4	475.8
Accumulated amortization	(297.5)	(213.9)	(214.1)
Indefinite-lived intangible assets	177.2	261.5	261.7
Intangible assets, gross	527.8	528.6	529.0
Accumulated amortization, net	(349.0)	(264.8)	(264.8)
Total intangible assets, net	178.8	263.8	264.2
Intangible liabilities, net
Gross carrying amount	(113.8)	(113.9)	(113.9)
Accumulated amortization	102.0	98.0	96.7
Total	$ (11.8)	$ (15.9)	$ (17.2)