Earnings (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018		Sep. 30, 2019	Sep. 30, 2018
Numerator for EPS - continuing operations
Income from continuing operations	$ 60.0	$ 185.8	[1]	$ 299.0	$ 256.0	[1],[2]
Less: Income from continuing operations attributed to non-controlling interest	8.7	6.5		20.3	20.9
Income from continuing operations attributable to Delek (numerator for basic EPS - continuing operations attributable to Delek)	51.3	179.3		278.7	235.1
Interest on Convertible Debt, Net of Tax	0.0	0.7		0.0	2.5
Numerator for diluted EPS - continuing operations attributable to Delek	51.3	180.0		278.7	237.6
Numerator for EPS - discontinued operations
Income (loss) from discontinued operations	0.0	0.5	[1]	(0.8)	(8.5)	[1],[2],[3]
Less: Income from discontinued operations attributed to non-controlling interest	0.0	0.0		0.0	8.1
Income (loss) from discontinued operations attributed to Delek	$ 0.0	$ 0.5		$ (0.8)	$ (16.6)
Denominator:
Weighted Average Number of Shares Outstanding( denominatior for basic EPS) (in shares)	75,028,562	83,575,122		76,463,435	83,294,473
Dilutive effect of convertible debt	0	2,176,140		0	2,183,186
Dilutive effect of warrants	0	1,683,722		0	1,291,156
Dilutive effect of stock-based awards	673,749	1,586,276		704,399	1,600,298
Weighted average common shares outstanding, assuming dilution (in shares)	75,702,311	89,021,260		77,167,834	88,369,113
EPS:
Income (loss) Income from Continuing Operations (USD per share)	$ 0.68	$ 2.15	[1]	$ 3.64	$ 2.82	[1],[2]
Loss from discontinued operations (USD per share)	0	0.01	[1]	(0.01)	(0.20)	[1],[2]
Total basic income (loss) per share (USD per Share)	0.68	2.16	[1]	3.63	2.62	[1],[2]
Income (Loss) from Continuing Operations (USD per share)	0.68	2.02	[1]	3.61	2.69	[1],[2]
Income (loss) from discontinued operations (USD per share)	0	0.01	[1]	(0.01)	(0.19)	[1],[2]
Total diluted income (loss) per share (USD per share)	$ 0.68	$ 2.03	[1]	$ 3.60	$ 2.50	[1],[2]
Stock Compensation Plan, Excluding Loss [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	1,846,919	1,014,057		2,003,283	1,208,648

[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.