The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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- Definition

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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- Definition

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			6 Months Ended		12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Change in Useful Life
Property, Plant and Equipment [Line Items]
Increase in depreciation expense	$ 18			$ 36
Common Units
Property, Plant and Equipment [Line Items]
Impact to basic net income per common unit (usd per unit)	$ (0.37)		$ 0.13	$ 0.14	$ (3.85)
Impact to diluted net income per common unit (usd per unit)	(0.37)		$ 0.13	0.14	$ (3.85)
Common Units \| Change in Useful Life
Property, Plant and Equipment [Line Items]
Impact to basic net income per common unit (usd per unit)	(0.02)			(0.05)
Impact to diluted net income per common unit (usd per unit)	$ (0.02)			$ (0.05)
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 \| Change in Useful 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 \| Change in Useful Life
Property, Plant and Equipment [Line Items]
Property and equipment, useful life		50 years