The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives and The noncash expense charged against earnings to recognize the consumption of natural resources that are not part of an entity's cost of goods sold.

No definition available.

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- Definition

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

+ References

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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

+ References

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-SubTopic 10
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- References

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Property, Plant and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, plant and equipment, net [Abstract]
Property, plant and equipment, gross	$ 2,256.0	$ 2,219.6
Less: accumulated depreciation and depletion	(1,153.1)	(1,158.3)
Property, plant and equipment, net	1,102.9	1,061.3
Depreciation and depletion expense	80.7	75.6	$ 75.4
Mineral Rights and Reserves [Member]
Property, plant and equipment, net [Abstract]
Property, plant and equipment, gross	582.8	545.9
Land [Member]
Property, plant and equipment, net [Abstract]
Property, plant and equipment, gross	47.3	44.5
Buildings [Member]
Property, plant and equipment, net [Abstract]
Property, plant and equipment, gross	219.3	199.6
Machinery and Equipment [Member]
Property, plant and equipment, net [Abstract]
Property, plant and equipment, gross	1,235.6	1,247.5
Furniture and Fixtures and Other [Member]
Property, plant and equipment, net [Abstract]
Property, plant and equipment, gross	134.8	132.3
Construction in Progress [Member]
Property, plant and equipment, net [Abstract]
Property, plant and equipment, gross	$ 36.1	$ 49.8