Goodwill and Other Intangible Assets (Goodwill Rollforward) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Beginning Balance	$ 1,559	$ 1,430
Ending Balance	1,555	1,559
Fuel Distribution and Marketing [Member]
Goodwill [Roll Forward]
Beginning Balance	881	752
Ending Balance	877	881
All Other [Member]
Goodwill [Roll Forward]
Beginning Balance	678	678
Ending Balance	678	678
7-Eleven Purchase [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		30
7-Eleven Purchase [Member] \| All Other [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		0
Superior Plus Corporation [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		10
Superior Plus Corporation [Member] \| All Other [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		0
Sandford Oil [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		31
Sandford Oil [Member] \| All Other [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		0
BRENCO [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		5
BRENCO [Member] \| All Other [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		0
American Midstream Partners, LP [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		44
Goodwil adjustments related to acquisition	(1)
Ending Balance	43
American Midstream Partners, LP [Member] \| Fuel Distribution and Marketing [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		44
Goodwil adjustments related to acquisition	(1)
American Midstream Partners, LP [Member] \| All Other [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		0
Goodwil adjustments related to acquisition	0
Schmitt Sales, Inc. [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		9
Goodwil adjustments related to acquisition	(3)
Ending Balance	6
Schmitt Sales, Inc. [Member] \| Fuel Distribution and Marketing [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		9
Goodwil adjustments related to acquisition	(3)
Schmitt Sales, Inc. [Member] \| All Other [Member]
Goodwill [Roll Forward]
Goodwill related to acquisition		$ 0
Goodwil adjustments related to acquisition	$ 0

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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