Income taxes - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Provision (benefit) for income taxes (in millions)	$ 37.3	$ 8.5	$ 81.0	$ (3.3)
Effective tax rate	43.00%	27.30%	44.20%	(2.50%)