Property, Plant and Equipment, Net - Property, Plant and Equipment, Net (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Abstract]
Land and land improvements	$ 1,231.9	$ 1,135.0
Mineral reserves and interests	2,529.7	2,509.8
Buildings	164.2	163.4
Machinery and equipment	4,782.0	4,548.6
Construction in progress	209.4	258.4
Finance lease right-of-use assets	37.8	18.3
Total property, plant and equipment	8,955.0	8,633.5
Less: accumulated depreciation, depletion and amortization	(3,712.7)	(3,427.5)
Property, plant and equipment, net	$ 5,242.3	$ 5,206.0

Land and land improvements gross.

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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 of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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Amount, after accumulated amortization, of right-of-use asset from finance lease.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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Carrying amount at the balance sheet date of mineral properties, gross of adjustments.

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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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