Loans, overdrafts and long-term debt - Loans, overdrafts and long-term debt (Details) - USD ($) $ in Millions	Oct. 31, 2020	Feb. 01, 2020	Nov. 02, 2019
Debt Instrument [Line Items]
Gross debt	$ 1,041.2	$ 613.1	$ 795.5
Less: Current portion of loans and overdrafts	(3.6)	(95.6)	(5.0)
Less: Unamortized debt issuance costs	(1.4)	(1.6)	(1.7)
Total long-term debt	1,036.2	515.9	788.8
Other loans and bank overdrafts
Debt Instrument [Line Items]
Gross debt	3.6	95.6	5.0
Senior Unsecured Notes Due in 2024 \| Senior Unsecured Notes
Debt Instrument [Line Items]
Gross debt	147.6	147.5	147.5
Senior Asset-Based Credit Facility \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Gross debt	790.0	270.0	543.0
Senior Asset-Based Credit Facility \| Line of Credit \| Term Loan Facility
Debt Instrument [Line Items]
Gross debt	$ 100.0	$ 100.0	$ 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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