Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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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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Pipeline Capacity

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Commitments and Contingencies (Details) $ in Millions	2 Months Ended	3 Months Ended		6 Months Ended	7 Months Ended	11 Months Ended	17 Months Ended	21 Months Ended	27 Months Ended
Commitments and Contingencies (Details) $ in Millions	Mar. 31, 2018 USD ($) bbl / d renewal MBbls	Mar. 31, 2018 USD ($) bbl / d renewal MBbls	Mar. 31, 2017 USD ($)	Mar. 31, 2018 USD ($) bbl / d renewal MBbls	Mar. 31, 2018 USD ($) bbl / d renewal MBbls	Dec. 31, 2018 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jan. 01, 2020 USD ($)	Dec. 31, 2017 USD ($)
Commitments and Contingencies (Textual)
MVP Terminal construction costs	$ 40,543	$ 40,543		$ 40,543	$ 40,543					$ 40,010
Contributions to MVP		55	$ 117
Cost of undivided interest in pipeline		$ 85	$ 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		2	2
Automatic renewal term of terminalling agreement		5 years
Minimum [Member]
Commitments and Contingencies (Textual)
Range of possible loss contingency	$ 0	$ 0		$ 0	$ 0
Maximum [Member]
Commitments and Contingencies (Textual)
Range of possible loss contingency	200	200		200	200
MVP Terminal [Member]
Commitments and Contingencies (Textual)
Contributions to MVP		42			123
MVP Terminal [Member] \| Magellan Midstream Partners LP (Magellan) [Member]
Commitments and Contingencies (Textual)
Long-term liability recorded	150	150		150	150
MVP Terminal [Member] \| Construction in Progress [Member]
Commitments and Contingencies (Textual)
MVP Terminal construction costs	$ 271	$ 271		$ 271	$ 271
MVP Terminal [Member] \| Expected [Member]
Commitments and Contingencies (Textual)
Contributions to MVP									$ 420
MVP Terminal [Member] \| Expected [Member] \| Minimum [Member] \| Construction in Progress [Member]
Commitments and Contingencies (Textual)
MVP Terminal construction costs									840
MVP Terminal [Member] \| Expected [Member] \| Maximum [Member] \| Construction in Progress [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%		40.00%	40.00%
Pipeline capacity (in barrels per day) \| bbl / d	150,000	150,000		150,000	150,000
Cost of undivided interest in pipeline		$ 17		$ 24
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%		20.00%	20.00%
Pipeline capacity (in barrels per day) \| bbl / d	500,000	500,000		500,000	500,000
Cost of undivided interest in pipeline	$ 68
Sunrise Pipeline System [Member] \| Expected [Member]
Commitments and Contingencies (Textual)
Cost of undivided interest in pipeline						$ 101	$ 135
Colorado City Storage Tanks [Member]
Commitments and Contingencies (Textual)
Approximate storage capacity of terminal (in barrels) \| MBbls	270	270		270	270
MVP Terminalling, LLC (MVP) [Member]
Commitments and Contingencies (Textual)
Membership percentage in VIE (percent)					50.00%