Leases - Balance sheet by asset category (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Lessee, Lease, Description [Line Items]
Operating lease ROU Asset	$ 44.9	$ 50.2
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent	Other Assets, Noncurrent
Property, plant and equipment, gross	$ 691.6	$ 677.2
Less: Accumulated depreciation	(436.8)	(429.0)
Property, plant and equipment, net	254.8	248.2	$ 196.8
Finance Leased Asset
Lessee, Lease, Description [Line Items]
Less: Accumulated depreciation	(6.8)	(7.1)
Property, plant and equipment, net	4.2	2.4
Finance Leased Automobile
Lessee, Lease, Description [Line Items]
Property, plant and equipment, gross	0.1	0.1
Finance Leased Machinery and Equipment
Lessee, Lease, Description [Line Items]
Property, plant and equipment, gross	10.9	9.4
Real Estate
Lessee, Lease, Description [Line Items]
Operating lease ROU Asset	39.4	45.9
Automobile
Lessee, Lease, Description [Line Items]
Operating lease ROU Asset	4.1	3.6
Machinery and equipment.
Lessee, Lease, Description [Line Items]
Operating lease ROU Asset	$ 1.4	$ 0.7