Property, Plants, and Equipment, Net (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Less: accumulated depreciation and amortization	$ 6,811	$ 6,769
Properties, plants and equipment excluding construction work in progress	4,950	4,965
Construction work-in-progress	777	739
Properties, plants, and equipment, net	5,727	5,704
Land and land rights
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	137	136
Structures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	2,357	2,364
Machinery and equipment:
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	9,267	9,234
Depreciable property, plant and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 11,761	$ 11,734

Properties plants and equipment excluding construction work in progress.

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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.

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- Definition

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.

+ References

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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