Properties, Plants and Equipment (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 4,499	$ 4,408
Accumulated depreciation	(1,089)	(1,059)
Net PP&E	3,410	3,349
Land
Property, Plant and Equipment [Line Items]
Gross PP&E	19	19
Buildings and improvements
Property, Plant and Equipment [Line Items]
Gross PP&E	94	94
Pipelines and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	1,447	1,424
Terminals and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	761	741
Rail racks and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	137	137
Processing and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	1,047	1,041
Caverns and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	585	585
Construction-in-progress
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 409	$ 367

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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