Warranty reserve - Components of Warranty Reserve (Details) - USD ($) $ in Millions	Jul. 29, 2023	Apr. 29, 2023	Jan. 28, 2023	Jul. 30, 2022	Apr. 30, 2022	Jan. 29, 2022
Other Liabilities Disclosure [Abstract]
Accrued expense and other current liabilities	$ 11.7		$ 11.3	$ 10.8
Other liabilities - non-current	31.2		29.5	27.7
Total warranty reserve	$ 42.9	$ 41.3	$ 40.8	$ 38.5	$ 37.7	$ 36.0