Properties, Plants, and Equipment, net (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 5,027		$ 5,010
Less: accumulated depreciation and amortization	2,701		2,626
Properties, plants and equipment excluding construction work in progress	2,326		2,384
Construction work-in-progress	189		208
Properties, plants, and equipment, net	2,515		2,592
Capital expenditures incurred but not yet paid	39	$ 29
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	1,025		1,033
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 3,910		$ 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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