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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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.

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Property, Plant, and Equipment, Net - Summary of Property, Plant, and Equipment, Net (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 8,992	$ 8,511
Less: Accumulated depreciation	(5,701)	(5,503)
Property, plant, and equipment, net	3,291	3,008	$ 2,784
Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	7,344	6,961
Building [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	914	875
Construction-in-progress [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	579	520
Land [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	119	119
Mineral rights [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 36	$ 36