Long-term debt - current and non-current - Schedule of available facilities (Details) € in Millions, $ in Millions, $ in Millions		3 Months Ended
	Jun. 05, 2026	Dec. 31, 2026	Sep. 30, 2026 CAD ($)	Sep. 30, 2026 EUR (€)	Sep. 30, 2026 USD ($)	Jun. 30, 2026 EUR (€)	May 31, 2026 USD ($)
Line of Credit \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument, line of credit						€ 300.0	$ 225.0
Term Loan B – EUR \| Secured Debt
Line of Credit Facility [Line Items]
Debt instrument, nominal amount \| €				€ 1,100.0
Term Loan B – EUR \| Secured Debt \| Forecast \| Subsequent Event
Line of Credit Facility [Line Items]
Basis spread on variable rate		1.75%
Floor interest rate		0.00%
Term Loan B – USD \| Secured Debt
Line of Credit Facility [Line Items]
Debt instrument, nominal amount					$ 1,339.5
Floor interest rate	1.75%
Term Loan B – USD \| Secured Debt \| Forecast \| Subsequent Event
Line of Credit Facility [Line Items]
Basis spread on variable rate		1.75%
Floor interest rate		0.00%
Term Facility - CAD \| Secured Debt
Line of Credit Facility [Line Items]
Debt instrument, nominal amount			$ 49.0
Term Facility - CAD \| Secured Debt \| Forecast \| Subsequent Event
Line of Credit Facility [Line Items]
Basis spread on variable rate		1.36%
Revolving Credit Facility (RCF) \| Line of Credit \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument, line of credit				210.0		210.0	140.0
Revolving Credit Facility (RCF) \| Line of Credit \| Revolving Credit Facility \| Forecast \| Subsequent Event
Line of Credit Facility [Line Items]
Basis spread on variable rate		2.00%
Ancillary Facility – ERSTE Bank \| Line of Credit \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument, line of credit				40.0		40.0	40.0
Ancillary Facility – ERSTE Bank \| Line of Credit \| Revolving Credit Facility \| Forecast \| Subsequent Event
Line of Credit Facility [Line Items]
Basis spread on variable rate		2.00%
Ancillary Facility – HELABA \| Line of Credit \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument, line of credit				€ 50.0		€ 50.0	$ 45.0
Ancillary Facility – HELABA \| Line of Credit \| Revolving Credit Facility \| Forecast \| Subsequent Event
Line of Credit Facility [Line Items]
Basis spread on variable rate		2.00%
Ancillary Facility – HELABA, Supplier Finance Program
Line of Credit Facility [Line Items]
Debt instrument, reverse factoring arrangement, amount					$ 39.7