Loans, overdrafts and long-term debt - Loans, overdrafts and long-term debt (Details) - USD ($) $ in Millions	May 01, 2021	Jan. 30, 2021	May 02, 2020
Debt Instrument [Line Items]
Gross debt	$ 147.6	$ 147.6	$ 1,359.7
Less: Current portion of loans and overdrafts	0.0	0.0	(22.2)
Less: Unamortized debt issuance costs	(0.8)	(0.9)	(1.5)
Total long-term debt	146.8	146.7	1,336.0
Other loans and bank overdrafts
Debt Instrument [Line Items]
Gross debt	0.0	0.0	22.2
Senior Unsecured Notes Due in 2024 \| Senior Unsecured Notes
Debt Instrument [Line Items]
Gross debt	147.6	147.6	147.5
Senior Asset-Based Credit Facility \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Gross debt	0.0	0.0	1,090.0
Senior Asset-Based Credit Facility \| Line of Credit \| Term Loan Facility
Debt Instrument [Line Items]
Gross debt	$ 0.0	$ 0.0	$ 100.0

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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