Revenues (Disaggregation of Revenue) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Disaggregation of Revenue [Line Items]
Revenue		$ 6,766.7	$ 4,456.0	$ 11,885.1	$ 7,993.1
Total petroleum product sales
Disaggregation of Revenue [Line Items]
Revenue	[1]	5,690.3	3,404.5	9,838.7	6,040.3
Petroleum product sales (at retail)
Disaggregation of Revenue [Line Items]
Revenue		5,082.9	3,062.5	8,811.3	5,447.3
Petroleum product sales (at wholesale)
Disaggregation of Revenue [Line Items]
Revenue		607.4	342.0	1,027.4	593.0
Merchandise sales
Disaggregation of Revenue [Line Items]
Revenue		994.6	963.4	1,886.6	1,796.6
RINs
Disaggregation of Revenue [Line Items]
Revenue		79.4	86.4	156.0	153.1
Other revenues
Disaggregation of Revenue [Line Items]
Revenue		2.4	1.7	3.8	3.1
Marketing | Marketing
Disaggregation of Revenue [Line Items]
Revenue		6,766.7	4,455.9	11,885.0	7,993.0
Marketing | Marketing | Total petroleum product sales
Disaggregation of Revenue [Line Items]
Revenue		5,690.3	3,404.5	9,838.7	6,040.3
Marketing | Marketing | Petroleum product sales (at retail)
Disaggregation of Revenue [Line Items]
Revenue		5,082.9	3,062.5	8,811.3	5,447.3
Marketing | Marketing | Petroleum product sales (at wholesale)
Disaggregation of Revenue [Line Items]
Revenue		607.4	342.0	1,027.4	593.0
Marketing | Marketing | Merchandise sales
Disaggregation of Revenue [Line Items]
Revenue		994.6	963.4	1,886.6	1,796.6
Marketing | Marketing | RINs
Disaggregation of Revenue [Line Items]
Revenue		79.4	86.4	156.0	153.1
Marketing | Marketing | Other revenues
Disaggregation of Revenue [Line Items]
Revenue		2.4	1.6	3.7	3.0
Corporate and Other Assets
Disaggregation of Revenue [Line Items]
Revenue		0.0	0.1	0.1	0.1
Corporate and Other Assets | Total petroleum product sales
Disaggregation of Revenue [Line Items]
Revenue		0.0	0.0	0.0	0.0
Corporate and Other Assets | Petroleum product sales (at retail)
Disaggregation of Revenue [Line Items]
Revenue		0.0	0.0	0.0	0.0
Corporate and Other Assets | Petroleum product sales (at wholesale)
Disaggregation of Revenue [Line Items]
Revenue		0.0	0.0	0.0	0.0
Corporate and Other Assets | Merchandise sales
Disaggregation of Revenue [Line Items]
Revenue		0.0	0.0	0.0	0.0
Corporate and Other Assets | RINs
Disaggregation of Revenue [Line Items]
Revenue		0.0	0.0	0.0	0.0
Corporate and Other Assets | Other revenues
Disaggregation of Revenue [Line Items]
Revenue		$ 0.0	$ 0.1	$ 0.1	$ 0.1

[1] Includes excise taxes of $554.7 million and $524.4 million for the three months ended June 30, 2022 and 2021, and $1,068.7 million and $994.0 million for the six months ended June 30, 2022 and 2021, respectively.