Redeemable preferred shares - Narrative (Details) - Series A Redeemable Convertible Preferred Stock - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
Oct. 05, 2016	Apr. 29, 2023	Apr. 30, 2022	Jan. 28, 2023
Temporary Equity [Line Items]
Redeemable convertible preferred stock, shares issued (in shares)	625,000
Preferred stock, purchase price	$ 625.0
Shares issued, price per share (usd per share)	$ 1,000
Preferred stock, dividend rate, percentage		5.00%
Payments of stock issuance costs	$ 13.7
Accumulated accretion of dividends		$ 11.1	$ 9.4	$ 10.7
Accretion to redemption value		$ 0.4	$ 0.4

Temporary Equity, Accumulated Accretion of Dividends

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

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Per share or per unit amount of equity securities issued.

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- Definition

Value of accretion of temporary equity to its redemption value during the period.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(27)(b))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Value of new stock classified as temporary equity issued during the period.

+ References

No definition available.

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