Goodwill and intangibles - Composition of Finite-Lived Intangibles (Details) - USD ($) $ in Millions	May 05, 2018	Feb. 03, 2018	Apr. 29, 2017
Intangible assets, net:
Gross carrying amount	$ 53.5	$ 49.8	$ 48.6
Accumulated amortization	(47.2)	(46.7)	(39.7)
Net carrying amount	6.3	3.1	8.9
Intangible assets, gross	530.1	528.2	451.6
Accumulated amortization, net	(47.2)	(46.7)	(39.7)
Total intangible assets, net	343.2	481.5	411.9
Definite-lived intangible liabilities:
Gross carrying amount	(114.1)	(114.5)	(113.5)
Accumulated amortization	87.1	85.2	76.2
Total	(27.0)	(29.3)	(37.3)
Trade names
Intangible assets, net:
Indefinite-lived intangible assets, gross	476.6	478.4	403.0
Accumulated amortization	(139.7)
Indefinite-lived intangible assets	$ 336.9	$ 478.4	$ 403.0

Finite-Lived Intangible Assets, Accumulated Amortization, Net

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Indefinite-Lived Intangible Assets, Accumulated Amortization

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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