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The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

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The cash outflow to purchase long lived physical asset for use in the normal oil and gas operations and to purchase mineral interests in oil and gas properties not intended for resale.

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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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The liability due as of the balance sheet date for leasebacks accounted for using the deposit method.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Term of the entity's agreement renewal option that may be requested.

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Represents the number of times an entity may request to renew or extend the term of an agreement or contract.

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Number of Properties

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Pipeline Capacity

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Terminal Storage Capacity

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Terminalling Agreement, Initial Term

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Undivided Ownership Interest in Assets Percentage

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Commitments and Contingencies (Details) $ in Millions	9 Months Ended		13 Months Ended	22 Months Ended	28 Months Ended
Commitments and Contingencies (Details) $ in Millions	Sep. 30, 2018 USD ($) bbl / d renewal property MBbls	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) bbl / d renewal MBbls	Jun. 30, 2019 USD ($)	Jan. 01, 2020 USD ($)	Dec. 31, 2017 USD ($)
Commitments and Contingencies (Textual)
MVP Terminal construction costs	$ 41,841		$ 41,841			$ 40,010
Contributions to MVP	124	$ 373
Cost of undivided interest in pipeline	$ 181	$ 72
Terminalling Agreement [Member] \| MVP Terminalling, LLC (MVP) [Member]
Commitments and Contingencies (Textual)
Initial term of terminal agreement	12 years
Number of available automatic renewals \| renewal	2		2
Automatic renewal term of terminalling agreement	5 years
MVP Terminal [Member]
Commitments and Contingencies (Textual)
Contributions to MVP	$ 107		$ 188
MVP Terminal [Member] \| Expected [Member]
Commitments and Contingencies (Textual)
Contributions to MVP					$ 420
MVP Terminal [Member] \| Magellan Midstream Partners LP (Magellan) [Member]
Commitments and Contingencies (Textual)
Long-term liability recorded	254		254
MVP Terminal [Member] \| Construction in Progress [Member]
Commitments and Contingencies (Textual)
MVP Terminal construction costs	$ 442		$ 442
MVP Terminal [Member] \| Minimum [Member] \| Construction in Progress [Member] \| Expected [Member]
Commitments and Contingencies (Textual)
MVP Terminal construction costs					840
MVP Terminal [Member] \| Maximum [Member] \| Construction in Progress [Member] \| Expected [Member]
Commitments and Contingencies (Textual)
MVP Terminal construction costs					$ 1,400
Central Texas Pipeline [Member]
Commitments and Contingencies (Textual)
Undivided interest in project (percent)	40.00%		40.00%
Pipeline capacity (in barrels per day) \| bbl / d	150,000		150,000
Cost of undivided interest in pipeline	$ 43		$ 50
Central Texas Pipeline [Member] \| Expected [Member]
Commitments and Contingencies (Textual)
Cost of undivided interest in pipeline				$ 170
Sunrise Pipeline System [Member]
Commitments and Contingencies (Textual)
Undivided interest in project (percent)	20.00%		20.00%
Pipeline capacity (in barrels per day) \| bbl / d	500,000		500,000
Cost of undivided interest in pipeline	$ 138
Colorado City Storage Tanks [Member]
Commitments and Contingencies (Textual)
Number of properties \| property	2
Approximate storage capacity of terminal (in thousands of barrels) \| MBbls	270		270
MVP Terminalling, LLC (MVP) [Member]
Commitments and Contingencies (Textual)
Membership percentage in VIE (percent)			50.00%