Fair value measurements (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Fair value measurements [Line Items]
Money market fund	$ 14.1	$ 163.5
Long-term debt	1,397.1	1,429.4
Long-term debt, fair value	1,433.1	1,476.8
Significant other observable inputs (Level 2) [Member]
Fair value measurements [Line Items]
Long-term debt, fair value	1,433.1	1,476.8
Fair Value, Recurring [Member]
Fair value measurements [Line Items]
Money market fund	14.1	163.5
Fair Value, Recurring [Member] \| Quoted prices in active markets for identical assets Level 1 [Member]
Fair value measurements [Line Items]
Money market fund	14.1	163.5
Proceeds receivable from asset sale (Note 6) [Member]
Fair value measurements [Line Items]
Long-term receivables	12.0
Long-term reeivables, fair value	12.0
Proceeds receivable from asset sale (Note 6) [Member] \| Significant unobservable inputs (Level 3) [Member]
Fair value measurements [Line Items]
Long-term reeivables, fair value	12.0
Loans and notes receivable from distributors [Member]
Fair value measurements [Line Items]
Long-term receivables	10.4	10.7
Long-term reeivables, fair value	10.8	11.9
Loans and notes receivable from distributors [Member] \| Significant unobservable inputs (Level 3) [Member]
Fair value measurements [Line Items]
Long-term reeivables, fair value	$ 10.8	$ 11.9

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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