Segment Data - Operating Performance (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	$ 1,821.2	$ 2,199.9
Operating costs and expenses:
Cost of materials and other	1,910.6	1,699.4
Operating expenses (excluding depreciation and amortization presented below)	154.5	166.7
Segment contribution margin	(243.9)	333.8
Depreciation and amortization	52.6	46.8
General and administrative expenses	65.7	62.2
Other operating (income) expense, net	(0.7)	2.4
Operating (loss) income	(361.5)	222.4
Capital spending (excluding business combinations)	190.2	128.4
Total assets	6,093.4		$ 7,016.3
Refining
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	1,569.3	1,907.4
Logistics
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	56.8	89.6
Retail
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	178.6	197.2
Operating Segments | Refining
Operating costs and expenses:
Operating expenses (excluding depreciation and amortization presented below)	111.7	121.0
Segment contribution margin	(290.4)	301.9
Depreciation and amortization	37.2	31.1
Capital spending (excluding business combinations)	168.1	81.7
Total assets	5,949.5
Operating Segments | Logistics
Operating costs and expenses:
Operating expenses (excluding depreciation and amortization presented below)	14.8	16.1
Segment contribution margin	47.3	40.1
Depreciation and amortization	6.3	6.5
Capital spending (excluding business combinations)	3.0	0.9
Total assets	946.3
Operating Segments | Retail
Operating costs and expenses:
Operating expenses (excluding depreciation and amortization presented below)	22.2	23.6
Segment contribution margin	12.3	10.2
Depreciation and amortization	2.9	4.3
Capital spending (excluding business combinations)	6.2	5.1
Total assets	312.1
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	16.5	5.7
Operating costs and expenses:
Operating expenses (excluding depreciation and amortization presented below)	5.8	6.0
Depreciation and amortization	6.2	4.9
Capital spending (excluding business combinations)	12.9	40.7
Corporate, Other and Eliminations
Operating costs and expenses:
Segment contribution margin	(13.1)	(18.4)
Total assets	(1,114.5)
Intersegment Eliminations
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	(265.2)	(247.5)
Intersegment Eliminations | Refining
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	(158.6)	(184.6)
Intersegment Eliminations | Logistics
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	(106.6)	(62.9)
Intersegment Eliminations | Retail
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	0.0	0.0
Product
Operating costs and expenses:
Cost of materials and other	1,910.6	1,699.4
Product | Operating Segments | Refining
Operating costs and expenses:
Cost of materials and other	1,906.6	1,669.1
Product | Operating Segments | Logistics
Operating costs and expenses:
Cost of materials and other	101.3	96.3
Product | Operating Segments | Retail
Operating costs and expenses:
Cost of materials and other	144.1	163.4
Product | Corporate, Non-Segment [Member]
Operating costs and expenses:
Cost of materials and other	(241.4)	(229.4)
Commodity Contract [Member]
Operating costs and expenses:
Net gains related to cash flow hedges	$ 1.8	13.1
Commodity Contract [Member] | Refining
Operating costs and expenses:
Net gains related to cash flow hedges		$ 7.6