Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Property, Plant and Equipment, net (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Property, Plant and Equipment
Cost	$ 695.3		$ 695.3		$ 682.7
Less accumulated depreciation	(505.1)		(505.1)		(491.2)
Total	190.2		190.2		191.5
Depreciation	11.8	$ 12.0	23.6	$ 24.0
Restructuring charges	0.1	6.5	0.3	10.4
Severance Pay and Contract Termination and Other Costs
Property, Plant and Equipment
Restructuring charges	0.1	7.4	0.3	$ 12.7
Severance Pay and Contract Termination and Other Costs \| Operating Segments \| Corporate, Non-Segment [Member]
Property, Plant and Equipment
Restructuring charges	0.0	$ 0.5
Land
Property, Plant and Equipment
Cost	13.2		13.2		8.0
Buildings and improvements
Property, Plant and Equipment
Cost	118.4		118.4		111.9
Machinery, equipment, and other
Property, Plant and Equipment
Cost	$ 563.7		$ 563.7		$ 562.8