Asset Impairment - Schedule of Asset Impairment (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Oct. 31, 2020	Aug. 01, 2020	May 02, 2020	Nov. 02, 2019	Aug. 03, 2019	Oct. 31, 2020	Nov. 02, 2019
Asset Impairment Charges [Abstract]
Goodwill impairment	$ 0.0			$ 0.0	$ 47.7	$ 10.7	$ 47.7
Indefinite-lived intangible asset impairment	0.0			0.0		83.3	0.0
Property and equipment impairment	1.5	$ 11.9	$ 13.8	0.0		27.2	0.0
Operating lease ROU asset impairment	0.0	$ 8.4	$ 28.5	0.0		36.9	0.0
Total impairment	1.5			$ 0.0		158.1	$ 47.7
Gain on termination or modification of lease	$ 0.9					$ 3.2

Gain (Loss) On Termination Or Modification Of Lease

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Amount of loss from impairment of right-of-use asset from operating lease.

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