Retirement plans - AOCI Items not yet Recognized (Details) - Pension plan - Foreign Plan - USD ($) $ in Millions	Jan. 28, 2023	Jan. 29, 2022	Jan. 30, 2021
Defined Benefit Plan Disclosure [Line Items]
Net actuarial gains (losses)	$ 3.9	$ (103.3)	$ (47.2)
Net prior service costs	$ 0.0	$ (3.9)	$ (4.0)

Amount, after tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI https://asc.fasb.org/extlink&oid=126968391&loc=SL7669686-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (j)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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- Definition

Amount, after tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (j)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI https://asc.fasb.org/extlink&oid=126968391&loc=SL7669686-108580

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- Definition

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.

+ References

No definition available.

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