Income taxes - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 23.7	$ 53.0	$ 55.2	$ 95.8
Effective tax rate	58.80%	58.60%	35.80%	40.80%

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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+ Details