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Derivative and hedging activities - other information (Details) € in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2024 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2025 EUR (€)	Nov. 30, 2025 EUR (€)	Apr. 30, 2023 USD ($)
Derivatives, Fair Value [Line Items]
Gross amount		$ 3,967,900,000	$ 4,077,800,000
Other Comprehensive Income (Loss), Cash Flow Hedge, Reclassification for Discontinuance, before Tax	$ 6,200,000
OCI, Cash Flow Hedge, Reclassification for Discontinuance, Statement of Income or Comprehensive Income [Extensible Enumeration]	Amount of gain or (loss) reclassified from AOCI into income
Net investment hedges
Derivatives, Fair Value [Line Items]
Amount of gain or (loss) recognized in OCI on Derivative		(89,900,000)	60,900,000
Cross-currency swaps \| Net investment hedges
Derivatives, Fair Value [Line Items]
Notional amount		750,000,000.0	750,000,000.0
Amount of gain or (loss) recognized in OCI on Derivative		(89,900,000)	60,900,000
Cross Currency Interest Rate Contract, Maturing In April 2027
Derivatives, Fair Value [Line Items]
Notional amount		250,000,000.0
Cross Currency Interest Rate Contract, Maturing In April 2028
Derivatives, Fair Value [Line Items]
Notional amount		250,000,000.0
Cross Currency Interest Rate Contract, Maturing In April 2029
Derivatives, Fair Value [Line Items]
Notional amount		$ 250,000,000.0
Interest Rate Swap
Derivatives, Fair Value [Line Items]
Notional amount	$ 750,000,000.0
Interest Rate Swap \| Conversion of SOFR Floating Rate To Fixed Rate
Derivatives, Fair Value [Line Items]
Notional amount						$ 100,000,000
3.875% unsecured notes \| Foreign exchange products \| Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Derivative liability \| €				€ 400.0	€ 144.0
Interest rate		3.875%		3.875%	3.875%
Gross amount \| €					€ 400.0
Amount of gain or (loss) recognized in OCI on Derivative		$ 3,000,000.0	$ 6,000,000.0