Fair value measurement - Fair Value of Assets and Liabilities (Details) - USD ($) $ in Millions	Aug. 02, 2025	Feb. 01, 2025	Aug. 03, 2024
Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 5.7	$ 5.6	$ 5.5
Liabilities	(1.8)	(0.7)	(0.4)
US Treasury securities \| Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	5.4	5.2	5.3
Foreign currency contracts \| Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.3	0.4	0.0
Liabilities	(1.8)	(0.7)	(0.4)
Corporate bonds and notes \| Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.0	0.0	0.2
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	5.4	5.2	5.3
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	5.4	5.2	5.3
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 \| Corporate bonds and notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.0	0.0	0.0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0.3	0.4	0.2
Liabilities	(1.8)	(0.7)	(0.4)
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	0.3	0.4	0.0
Liabilities	(1.8)	(0.7)	(0.4)
Level 2 \| Corporate bonds and notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 0.0	$ 0.0	$ 0.2