Properties, Plants, and Equipment, net (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 4,968		$ 5,010
Less: accumulated depreciation and amortization	2,644		2,626
Properties, plants and equipment excluding construction work in progress	2,324		2,384
Construction work-in-progress	200		208
Properties, plants, and equipment, net	2,524		2,592
Capital expenditures incurred but not yet paid	28	$ 48
Land and land rights
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	92		98
Structures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,020		1,033
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 3,856		$ 3,879

Properties plants and equipment excluding construction work in progress.

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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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Future cash outflow to pay for purchases of fixed assets that have occurred.

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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 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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