Properties, Plants and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 4,408	$ 3,995
Accumulated depreciation	(1,059)	(943)
Net PP&E	3,349	3,052
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	89
Buildings and improvements \| Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Buildings and improvements \| Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	30 years
Pipelines and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 1,424	1,398
Pipelines and related assets \| Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	10 years
Pipelines and related assets \| Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	45 years
Terminals and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 741	710
Terminals and related assets \| Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	25 years
Terminals and related assets \| Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	45 years
Rail racks and related assets
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	33 years
Gross PP&E	$ 137	137
Processing and related assets
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	25 years
Gross PP&E	$ 1,041	842
Caverns and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 585	584
Caverns and related assets \| Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	25 years
Caverns and related assets \| Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	45 years
Construction-in-progress
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 367	$ 216

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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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