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Property, plant and equipment (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Property, plant and equipment
Property, plant and equipment, gross		$ 1,511.5	$ 1,337.6
Accumulated depreciation and impairment charges		(744.7)	(629.5)
Property, plant and equipment, net		766.8	708.1
Depreciation		109.1	105.7	$ 94.6
Impairment charges		785.0	0.0	$ 160.8
Ritter GmbH \| Property, Plant and Equipment \| Bioscience Production
Property, plant and equipment
Impairment charges	$ 54.4
Buildings and related improvements
Property, plant and equipment
Property, plant and equipment, gross		458.7	414.3
Machinery, equipment and other
Property, plant and equipment
Property, plant and equipment, gross		643.3	544.3
Software
Property, plant and equipment
Property, plant and equipment, gross		268.3	238.9
Land
Property, plant and equipment
Property, plant and equipment, gross		57.6	53.9
Assets not yet placed into service
Property, plant and equipment
Property, plant and equipment, gross		$ 83.6	$ 86.2