Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount after accumulated impairment loss of an asset representing 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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Goodwill and intangibles - Additional Information (Details) - USD ($) $ in Millions		3 Months Ended
	Mar. 29, 2021	May 01, 2021	May 02, 2020	Jan. 30, 2021
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment		$ 0.0	$ 10.7
Indefinite-lived intangible asset impairment		0.0	83.3
Goodwill		244.9	238.0	$ 238.0
North America
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment			10.7
Goodwill acquired		6.9
Goodwill		$ 244.9		$ 238.0
North America \| Rocksbox
Finite-Lived Intangible Assets [Line Items]
Definite-lived intangible assets acquired	$ 11.5
Goodwill acquired	$ 6.9
Acquired finite-lived intangible assets, weighted average useful life	8 years
North America \| Certain Zales Trade Names
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible asset impairment			$ 83.3