Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Net revenues	$ 2,062.9	$ 2,334.3	$ 5,419.6	$ 7,014.5
Cost of sales:
Cost of materials and other	1,875.9	1,964.1	5,064.3	5,731.2
Operating expenses (excluding depreciation and amortization presented below)	115.7	141.7	348.3	418.4
Depreciation and amortization	59.4	43.8	160.0	125.7
Total cost of sales	2,051.0	2,149.6	5,572.6	6,275.3
Operating expenses related to retail and wholesale business (excluding depreciation and amortization presented below)	24.0	25.2	73.7	77.5
General and administrative expenses	57.0	65.6	184.4	197.3
Depreciation and amortization	5.8	6.0	17.4	21.0
Other operating loss (income), net	0.3	0.5	(14.6)	(0.7)
Total operating costs and expenses	2,138.1	2,246.9	5,833.5	6,570.4
Operating (loss) income	(75.2)	87.4	(413.9)	444.1
Interest expense	31.9	33.9	98.0	95.4
Interest income	(0.9)	(3.2)	(3.1)	(9.0)
Income from equity method investments	(12.8)	(16.5)	(28.6)	(28.4)
Loss (gain) on sale of non-operating refinery	0.1	0.0	(56.8)	0.0
Other (income) expense, net	(1.0)	(0.2)	(3.4)	3.3
Total non-operating expense, net	17.3	14.0	6.1	61.3
(Loss) income before income tax (benefit) expense	(92.5)	73.4	(420.0)	382.8
Income tax (benefit) expense	(15.6)	13.4	(134.6)	83.8
(Loss) income from continuing operations, net of tax	(76.9)	60.0	(285.4)	299.0
Discontinued operations:
Loss from discontinued operations, including loss on sale of discontinued operations	0.0	0.0	0.0	(1.0)
Income tax benefit	0.0	0.0	0.0	(0.2)
Loss from discontinued operations, net of tax	0.0	0.0	0.0	(0.8)
Net (loss) income	(76.9)	60.0	(285.4)	298.2
Net income attributed to non-controlling interests	11.2	8.7	29.4	20.3
Net (loss) income attributable to Delek US	$ (88.1)	$ 51.3	$ (314.8)	$ 277.9
Basic (loss) income per share:
(Loss) income from continuing operations (USD per share)	$ (1.20)	$ 0.68	$ (4.28)	$ 3.64
Loss from discontinued operations (USD per share)	0	0	0	(0.01)
Basic income (loss) per share (USD per Share)	(1.20)	0.68	(4.28)	3.63
Diluted (loss) income per share:
(Loss) income from continuing operations (USD per share)	(1.20)	0.68	(4.28)	3.61
Loss from discontinued operations (USD per share)	0	0	0	(0.01)
Diluted income (loss) per share (USD per share)	(1.20)	0.68	(4.28)	3.60
Dividends declared per common share outstanding (in dollars per share)	$ 0.31	$ 0.29	$ 0.93	$ 0.84