Lease expenses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Lessee, Lease, Description [Line Items]
Variable lease costs	$ 27.1	$ 25.9
Cash paid for operating leases	122.2	133.0
Leased assets obtained in exchange for new operating lease liabilities	96.0	56.1
Operating	227.5	221.3
Income Statement Location [Axis]: us-gaap:DirectOperatingCosts
Lessee, Lease, Description [Line Items]
Operating lease expenses	111.4	109.4
Income Statement Location [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense
Lessee, Lease, Description [Line Items]
Operating lease expenses	$ 3.2	$ 2.9