Segment Data - Operating Performance (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018		Sep. 30, 2019	Sep. 30, 2018		Dec. 31, 2018
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	$ 2,334.3	$ 2,768.9	[1]	$ 7,014.5	$ 7,759.0	[1],[2]
Inter-segment fees and revenues	0.0	0.0		0.0	0.0
Operating costs and expenses:
Cost of materials and other	1,964.1	2,244.2	[1]	5,731.2	6,537.2	[1],[2]
Operating expenses (excluding depreciation and amortization presented below)	166.9	164.0		495.9	479.6
Segment contribution margin	203.3	360.7		787.4	742.2
Depreciation and amortization	49.8	49.2		146.7	146.4	[3]
General and administrative expenses	65.6	58.0	[1]	197.3	176.1	[1],[2]
Other operating expense (income), net	0.5	(1.7)	[1]	(0.7)	(9.4)	[1],[2]
Operating income	87.4	255.2	[1]	444.1	429.1	[1],[2]
Total assets	6,793.3			6,793.3			$ 5,760.6
Capital spending (excluding business combinations)	110.5	86.1		324.8	210.9
Operating Segments | Refining
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	2,036.9	2,420.5		6,096.7	6,678.2
Operating costs and expenses:
Cost of materials and other	1,928.6	2,211.0		5,679.8	6,341.9
Operating expenses (excluding depreciation and amortization presented below)	120.7	118.8		356.7	346.7
Segment contribution margin	127.5	319.5		600.1	629.8
Depreciation and amortization	34.6	33.8		98.9	99.1
Total assets	7,036.8			7,036.8
Capital spending (excluding business combinations)	63.3	51.1		193.8	136.3
Operating Segments | Logistics
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	71.4	100.3		254.3	319.8
Operating costs and expenses:
Cost of materials and other	72.6	105.6		262.7	330.6
Operating expenses (excluding depreciation and amortization presented below)	18.4	15.4		51.8	42.9
Segment contribution margin	46.6	43.1		130.9	124.8
Depreciation and amortization	6.6	6.7		19.8	19.7
Total assets	767.8			767.8
Capital spending (excluding business combinations)	4.0	2.9		6.2	7.4
Operating Segments | Retail
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	218.5	246.4		640.2	700.8
Operating costs and expenses:
Cost of materials and other	176.4	204.4		521.9	578.5
Operating expenses (excluding depreciation and amortization presented below)	23.5	26.7		71.9	76.5
Segment contribution margin	18.6	15.3		46.4	45.8
Depreciation and amortization	3.0	5.3		11.5	16.8
Total assets	354.2			354.2
Capital spending (excluding business combinations)	3.8	1.9		14.3	6.0
Corporate, Other and Eliminations
Segment Reporting Information [Line Items]
Net revenues (excluding inter-segment fees and sales)	7.5	1.7		23.3	60.2
Operating costs and expenses:
Cost of materials and other	(213.5)	(276.8)		(733.2)	(713.8)
Operating expenses (excluding depreciation and amortization presented below)	4.3	3.1		15.5	13.5
Segment contribution margin	10.6	(17.2)		10.0	(58.2)
Depreciation and amortization	5.6	3.4		16.5	10.8
Capital spending (excluding business combinations)	39.4	30.2		110.5	61.2
Intersegment Eliminations
Segment Reporting Information [Line Items]
Inter-segment fees and revenues	(206.1)	(292.6)		(731.0)	(818.7)
Intersegment Eliminations | Refining
Segment Reporting Information [Line Items]
Inter-segment fees and revenues	139.9	228.8		539.9	640.2
Intersegment Eliminations | Logistics
Segment Reporting Information [Line Items]
Inter-segment fees and revenues	66.2	63.8		191.1	178.5
Intersegment Eliminations | Retail
Segment Reporting Information [Line Items]
Inter-segment fees and revenues	$ 0.0	0.0		$ 0.0	0.0
Restatement Adjustment [Member]
Footnote:
Net Revenue, Cost Of Materials And Other		$ 273.7			$ 347.1

[1] Net revenues and cost of materials and other for the three and nine months ended September 30, 2018 reflect a correction of an intercompany elimination which resulted in an increase in those accounts of $273.7 million and $347.1 million, respectively, not previously reflected on the unaudited consolidated financial statements in our September 30, 2018 Quarterly Report on Form 10-Q filed on November 9, 2018. Such amounts are not considered material to the financial statements and had no impact to operating income or net income for those periods. See Note 23 to our annual audited consolidated financial statements included in Part II, Item 8 of our 2018 Annual Report on Form 10-K, as amended and filed on June 27, 2019, for further discussion.

[2] Income tax expense for the nine months ended September 30, 2018 reflects a correction made in our 2018 Annual Report on Form 10-K (as originally filed on March 1, 2019) to record additional deferred tax expense totaling $5.5 million related to the recognition of a valuation allowance on deferred tax assets recognized in connection with the Big Spring Logistic Assets Acquisition (see Note 5) not previously reported in our September 30, 2018 Quarterly Report on Form 10-Q filed on November 09, 2018. Such amount is not considered material to the financial statements or the trend of earnings for that period. See Note 23 to our annual audited consolidated financial statements included in Part II, Item 8 of our 2018 Annual Report on Form 10-K, as amended and filed on June 27, 2019, for further discussion.

[3] Net income and deferred income taxes for the nine months ended September 30, 2018 reflects a correction made in our 2018 Annual Report on Form 10-K (as originally filed on March 1, 2019) to record additional deferred tax expense totaling $5.5 million related to the recognition of a valuation allowance on deferred tax assets recognized in connection with the Big Spring Logistic Assets Acquisition (see Note 5) not previously reported in our September 30, 2018 Quarterly Report on Form 10-Q filed on November 09, 2018. Such amount is not considered material to the financial statements or the trend of earnings for that period. See Note 23 to our annual audited consolidated financial statements included in Part II, Item 8 of our 2018 Annual Report on Form 10-K, as amended and filed on June 27, 2019, for further discussion.