Acquisitions and Divestment - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	May 31, 2019 USD ($)	Jan. 18, 2019 USD ($)	Dec. 20, 2018 USD ($)	Dec. 18, 2018 USD ($) gal	Oct. 16, 2018 USD ($) gal	Aug. 01, 2018 USD ($) gal	Apr. 25, 2018 USD ($)	Apr. 02, 2018 USD ($) stores	Dec. 31, 2017 USD ($)	Jan. 18, 2017 stores
Business Acquisition [Line Items]
Goodwill	$ 1,555	$ 1,559									$ 1,430
Number of stores | stores												97
Loss Contingency, Loss in Period	8
Speedway LLC [Member]
Business Acquisition [Line Items]
Purchase price				$ 5
American Midstream Partners, LP [Member]
Business Acquisition [Line Items]
Purchase price					$ 127
Number of Terminal Tanks					21
Storage Capacity in Barrels					1,300,000
Barrels of Throughput Capacity					77,500
Goodwill	43				$ 43
Change in goodwill		44
Schmitt Sales, Inc. [Member]
Business Acquisition [Line Items]
Purchase price						$ 46
Number of Gallons Distributed | gal						180,000,000
Goodwill	$ 6					$ 6
Change in goodwill		9
BRENCO [Member]
Business Acquisition [Line Items]
Purchase price							$ 26
Number of Gallons Distributed | gal							95,000,000
Number of Dealer-Operated Locations							160
Number of Commercial Accounts							100
Goodwill							$ 5
Change in goodwill		5
Sandford Oil [Member]
Business Acquisition [Line Items]
Purchase price								$ 93
Number of Gallons Distributed | gal								115,000,000
Goodwill								$ 31
Change in goodwill		31
Superior Plus Corporation [Member]
Business Acquisition [Line Items]
Purchase price									$ 58
Number of Dealer-Operated Locations									100
Number of Terminals									3
Goodwill									$ 10
Change in goodwill		10
7-Eleven Purchase [Member]
Business Acquisition [Line Items]
Purchase price										$ 54
Goodwill										$ 30
Change in goodwill		$ 30
Number of stores | stores										26
Fulton Ethanol Plant [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Business Acquisition [Line Items]
Consideration received from divestiture			$ 20