Goodwill and intangibles - Summary of Goodwill (Details) - USD ($) $ in Millions	6 Months Ended
Jul. 31, 2021	Jan. 30, 2021
Goodwill [Roll Forward]
Beginning balance	$ 238.0
Ending balance	245.1
North America
Goodwill [Roll Forward]
Beginning balance	238.0
Acquisitions	7.1
Ending balance	245.1
Goodwill, accumulated impairment loss	$ 576.0	$ 576.0

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 increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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