Retirement plans - Fair Value of Unfunded, Non-qualified Deferred Compensation Plans Assets (Details) - USD ($) $ in Millions	Feb. 01, 2025	Feb. 03, 2024
Defined Contribution Plan Disclosure [Line Items]
Deferred compensation plan assets	$ 31.0	$ 25.2
Mutual funds
Defined Contribution Plan Disclosure [Line Items]
Deferred compensation plan assets	28.3	22.4
Level 1
Defined Contribution Plan Disclosure [Line Items]
Deferred compensation plan assets	28.3	22.4
Level 1 | Mutual funds
Defined Contribution Plan Disclosure [Line Items]
Deferred compensation plan assets	28.3	22.4
NAV | Money market mutual funds
Defined Contribution Plan Disclosure [Line Items]
Deferred compensation plan assets	$ 2.7	$ 2.8