Long-Term Obligations and Notes Payable Debt Maturity Schedule (Details) $ in Millions	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
2019	$ 32.0
2020	62.0
2021	27.0
2022	7.0
2023	763.7
Thereafter	909.8
Total	1,801.5
Revolving Credit Facility
Debt Instrument [Line Items]
2019	0.0
2020	0.0
2021	0.0
2022	0.0
2023	300.0
Thereafter	0.0
Total	300.0
Term Loan Credit Facility
Debt Instrument [Line Items]
2019	7.0
2020	7.0
2021	7.0
2022	7.0
2023	7.0
Thereafter	659.8
Total	694.8
Delek Logistics Credit Facility
Debt Instrument [Line Items]
2019	0.0
2020	0.0
2021	0.0
2022	0.0
2023	456.7
Thereafter	0.0
Total	456.7
Delek Logistics Notes
Debt Instrument [Line Items]
2019	0.0
2020	0.0
2021	0.0
2022	0.0
2023	0.0
Thereafter	250.0
Total	250.0
Reliant Bank Revolver
Debt Instrument [Line Items]
2019	0.0
2020	30.0
2021	0.0
2022	0.0
2023	0.0
Thereafter	0.0
Total	30.0
Promissory Notes
Debt Instrument [Line Items]
2019	25.0
2020	25.0
2021	20.0
2022	0.0
2023	0.0
Thereafter	0.0
Total	$ 70.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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