Fair Value Inputs used in the annual goodwill impairment test

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Total Number of Reporting Units including reporting units that don't have goodwill assigned.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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- Definition

Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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.

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No definition available.

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

No definition available.

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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

+ References

No definition available.

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- Definition

Amount of goodwill allocated to reporting unit with zero or negative amount of net assets.

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Goodwill and Intangibles Goodwill (Details)		3 Months Ended	9 Months Ended	12 Months Ended
Goodwill and Intangibles Goodwill (Details)	Nov. 30, 2019	Mar. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jul. 31, 2020 USD ($)	Dec. 31, 2018 USD ($)
Goodwill [Line Items]
Goodwill, Gross			$ 10,798,000,000			$ 10,146,000,000
Goodwill, Impaired, Accumulated Impairment Loss			(3,141,000,000)			(130,000,000)
Goodwill		$ (7,700,000,000)	(7,657,000,000)	$ (9,536,000,000)		(10,016,000,000)
Goodwill, Impairment Loss			(1,814,000,000)	(1,197,000,000)
Goodwill, Acquired During Period				717,000,000
Total Number of Reporting Units		6
Reporting Unit, Zero or Negative Carrying Amount, Amount of Allocated Goodwill				1
Number of Reporting Units	6	4
Crude Gathering [Member]
Goodwill [Line Items]
Goodwill		$ (1,100,000,000)
Minimum [Member]
Goodwill [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount		8.50%
Maximum [Member]
Goodwill [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount		270.00%
L&S
Goodwill [Line Items]
Goodwill, Gross			7,657,000,000			7,234,000,000
Goodwill, Impaired, Accumulated Impairment Loss			0			0
Goodwill			(7,657,000,000)	(7,722,000,000)		(7,234,000,000)
Goodwill, Impairment Loss			0	0
Goodwill, Acquired During Period				488,000,000
G&P
Goodwill [Line Items]
Goodwill, Gross			3,141,000,000			2,912,000,000
Goodwill, Impaired, Accumulated Impairment Loss			(3,141,000,000)			(130,000,000)
Goodwill			0	(1,814,000,000)		$ (2,782,000,000)
Goodwill, Impairment Loss		$ (1,814,000,000)	$ (1,814,000,000)	(1,197,000,000)
Goodwill, Acquired During Period				$ 229,000,000
Valuation, Income Approach [Member] \| Measurement Input, Discount Rate [Member] \| Goodwill [Member] \| Minimum [Member]
Goodwill [Line Items]
Fair Value Inputs		9.50%
Valuation, Income Approach [Member] \| Measurement Input, Discount Rate [Member] \| Goodwill [Member] \| Maximum [Member]
Goodwill [Line Items]
Fair Value Inputs		11.50%
Western Refining Wholesale & Western Refining Product Transport [Member]
Goodwill [Line Items]
Goodwill					$ (65,000,000)
Western Refining Wholesale & Western Refining Product Transport [Member] \| L&S
Goodwill [Line Items]
Goodwill					(65,000,000)
Western Refining Wholesale & Western Refining Product Transport [Member] \| G&P
Goodwill [Line Items]
Goodwill					$ 0