Derivative and hedging activities - Effect on AOCI (Details) - Net Investment Hedging - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of gain or (loss) recognized in OCI on Derivative	$ 20.8	$ (30.4)
Amount of gain or (loss) recognized in income on Derivative (amount excluded from effectiveness testing)	1.9	3.2
Cross-currency swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of gain or (loss) recognized in OCI on Derivative	20.8	(30.4)
Cross-currency swaps | Interest expense, net
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of gain or (loss) recognized in income on Derivative (amount excluded from effectiveness testing)	$ 1.9	$ 3.2