Share-based compensation - Schedule of Activity of Stock Options Granted under Omnibus Plan (Details) - Omnibus Plan - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Feb. 01, 2025	Feb. 03, 2024
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning Balance (in shares)	0.1
Exercised	0.0
Ending Balance (in shares)	0.1	0.1
Weighted average exercise price
Beginning Balance (usd per share)	$ 38.31
Exercised	0
Ending Balance (usd per share)	$ 37.66	$ 38.31
Weighted average remaining contractual life	3 years 4 months 24 days	4 years 3 months 18 days
Intrinsic value	$ 1.3	$ 6.4

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

+ References

No definition available.

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- References

No definition available.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 718
-SubTopic 10
-Subparagraph (e)(1)
-Name Accounting Standards Codification
-Paragraph 2
-Section 50
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Number of options vested.

+ References

No definition available.

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- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

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