Fair value measurement - Fair Value of Assets and Liabilities (Details) - USD ($) $ in Millions	Aug. 01, 2026	Jan. 31, 2026	Aug. 02, 2025
Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 5.8	$ 32.9	$ 5.7
Liabilities	(11.0)	(1.0)	(1.8)
US Treasury securities \| Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	5.3	5.4	5.4
Foreign currency contracts \| Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.5	0.7	0.3
Liabilities	(0.2)	(0.4)	(1.8)
Commodity Contracts \| Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.0	26.8	0.0
Liabilities	(10.8)	(0.6)	0.0
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	5.3	5.4	5.4
Liabilities	0.0	0.0	0.0
Level 1 \| US Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	5.3	5.4	5.4
Level 1 \| Foreign currency contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.0	0.0	0.0
Liabilities	0.0	0.0	0.0
Level 1 \| Commodity Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.0	0.0	0.0
Liabilities	0.0	0.0	0.0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.5	27.5	0.3
Liabilities	(11.0)	(1.0)	(1.8)
Level 2 \| US Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.0	0.0	0.0
Level 2 \| Foreign currency contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.5	0.7	0.3
Liabilities	(0.2)	(0.4)	(1.8)
Level 2 \| Commodity Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.0	26.8	0.0
Liabilities	$ (10.8)	$ (0.6)	$ 0.0