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Debt - other information (Details) - USD ($) $ in Millions			1 Months Ended	3 Months Ended		6 Months Ended
Debt - other information (Details) - USD ($) $ in Millions	Jul. 06, 2026	Jun. 30, 2026	Oct. 31, 2025	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Debt Instrument [Line Items]
Interest income				$ 10.3	$ 11.0	$ 20.8	$ 18.9
Debt issuance costs, net		$ 17.6	$ 8.0	17.6		17.6		$ 21.6
Gross amount		3,715.4		3,715.4		3,715.4		3,967.9
Amortization of deferred financing costs			4.4			3.5	4.5
Loss on extinguishment of debt				0.6	$ 0.0	1.2	$ 0.0
Amended Revolving Credit Facility Mature In October 2030 \| Revolving credit facility
Debt Instrument [Line Items]
Revolving credit facility, maximum borrowing capacity		1,400.0		1,400.0		$ 1,400.0
Revolving credit facility
Debt Instrument [Line Items]
Debt issuance costs, net			3.8
Revolving credit facility, maximum borrowing capacity			$ 1,400.0
Senior secured credit facilities: \| Euro term loans B-6 \| Euro
Debt Instrument [Line Items]
Interest terms						2.50%
Gross amount		$ 427.1		$ 427.1		$ 427.1		$ 645.2
Repayments of debt						102.5
Loss on extinguishment of debt						$ 0.6
Senior Loans \| Term Loan Mature In October 2032
Debt Instrument [Line Items]
Interest terms		1.50%
Senior Loans \| Term Loan Mature In October 2030
Debt Instrument [Line Items]
Interest terms		2.50%
Senior Loans \| Term Loan Mature In October 2030 \| Subsequent Event
Debt Instrument [Line Items]
Interest terms	2.00%