Property, Plant and Equipment - Components of property, plant and equipment (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment
Total cost	$ 740.4	$ 756.1
Less accumulated depreciation	(457.6)	(461.8)
Property, plant and equipment — net	282.8	294.3
Land
Property, Plant and Equipment
Total cost	19.9	20.3
Building and Improvements
Property, Plant and Equipment
Total cost	201.5	203.7
Machinery, Equipment and Tooling
Property, Plant and Equipment
Total cost	292.0	292.6
Furniture and Fixtures
Property, Plant and Equipment
Total cost	14.8	21.0
Computer Hardware and Software
Property, Plant and Equipment
Total cost	125.6	119.3
Rental Cranes
Property, Plant and Equipment
Total cost	75.3	90.2
Construction in Progress
Property, Plant and Equipment
Total cost	$ 11.3	$ 9.0

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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