Income taxes - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Tax Disclosure [Abstract]
Provision (benefit) for income taxes (in millions)	$ 23.4	$ 29.3	$ 43.7	$ (11.8)
Effective tax rate	39.90%	43.40%	45.30%	(11.70%)