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Debt - Components of debt (Details) - USD ($) $ in Millions	Dec. 31, 2025	Jun. 17, 2025	Dec. 31, 2024	Oct. 01, 2024	Aug. 26, 2024	Apr. 06, 2021
Debt Instrument [Line Items]
Finance leases	$ 1.9		$ 7.1
Debt and finance leases	1,538.4		1,707.1
Less: unamortized debt issuance costs	(15.6)		(18.2)
Total debt	1,522.8		1,688.9
Revolving credit facility \| Revolving credit facility
Debt Instrument [Line Items]
Revolving credit facility	0.0		0.0
Less: unamortized debt issuance costs	(2.7)
Term Loan
Debt Instrument [Line Items]
Long-term debt, gross	536.5	$ 698.3	700.0	$ 700.0
Senior Notes due 2029 \| Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	400.0		400.0			$ 400.0
Senior Notes due 2032 \| Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 600.0		$ 600.0		$ 600.0