The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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Per unit of ownership amount after tax of income (loss) available to limited partnership (LP) unit-holder and units that would have been outstanding assuming the issuance of limited partner units for dilutive potential units outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

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Per unit of ownership amount after tax of income (loss) available to outstanding limited partnership (LP) unit-holder.

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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.

+ References

No definition available.

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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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Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Depreciation and amortization	$ 177	$ 168
Service Life
Property, Plant and Equipment [Line Items]
Depreciation and amortization	$ 18
Common Units
Property, Plant and Equipment [Line Items]
Basic net income/(loss) per common unit (usd per unit)	$ 0.51	$ (3.98)
Diluted net income/(loss) per common unit (usd per unit)	0.51	$ (3.98)
Common Units \| Service Life
Property, Plant and Equipment [Line Items]
Basic net income/(loss) per common unit (usd per unit)	(0.03)
Diluted net income/(loss) per common unit (usd per unit)	$ (0.03)
Pipeline and related facilities and Storage, terminal and rail facilities \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life			10 years
Pipeline and related facilities and Storage, terminal and rail facilities \| Minimum \| Service Life
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	10 years
Pipeline and related facilities and Storage, terminal and rail facilities \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life			70 years
Pipeline and related facilities and Storage, terminal and rail facilities \| Maximum \| Service Life
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	50 years