Long-Term Obligations and Notes Payable - Line of Credit Narrative (Details) $ in Millions			3 Months Ended
	Oct. 26, 2018	Mar. 30, 2018 USD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	[1]	Dec. 31, 2018 USD ($)	Sep. 28, 2018 USD ($)	Sep. 27, 2018 USD ($)	Mar. 30, 2018 CAD ($)
Debt Instrument [Line Items]
Gain (Loss) on Extinguishment of Debt			$ 0	$ (9,000,000.0)
Outstanding borrowings			1,761,100,000			$ 1,783,300,000
Letter of credit
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 226,400,000
Line of credit | Revolving credit facility
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 1,000,000,000.0							$ 50.0
Debt Instrument, Weighted Average Borrowing Rate			5.75%
Outstanding borrowings			$ 300,000,000.0
Letters of credit outstanding			226,400,000
Remaining borrowing capacity			473,600,000
Line of credit | Revolving credit facility | DKL Revolver
Debt Instrument [Line Items]
Outstanding borrowings			461,200,000			456,700,000
Line of credit | Revolving credit facility | Wells Revolving Loan
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 450,000,000.0
Line of credit | Revolving credit facility | Reliant Bank Revolver
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 30,000,000.0
Commitment fee percentage (as percent)			0.50%
Outstanding borrowings			$ 30,000,000.0			$ 30,000,000.0
Remaining borrowing capacity			0
Line of credit | Revolving credit facility | Base Rate
Debt Instrument [Line Items]
Basis spread (as percent)		0.25%
Line of credit | Revolving credit facility | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread (as percent)		1.25%
Term loan
Debt Instrument [Line Items]
Face amount of debt		$ 700,000,000.0
Maximum borrowing capacity			693,000,000.0
Debt Instrument, Original Debt Issue Discount		0.50%							0.50%
Proceeds from term loan		$ 300,000,000.0
Gain (Loss) on Extinguishment of Debt			$ 9,000,000.0
Principal installments		$ 1,750,000
Debt Instrument, Prepayment Premium		1.00%							1.00%
Debt Instrument, Weighted Average Borrowing Rate			4.75%
Term loan | Base Rate
Debt Instrument [Line Items]
Basis spread (as percent)		1.50%
Term loan | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread (as percent)		2.50%
Letter of credit
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 300,000,000.0							$ 10.0
Fifth Third Bank | Line of credit | Revolving credit facility | DKL Revolver
Debt Instrument [Line Items]
Maximum borrowing capacity							$ 850,000,000.0	$ 700,000,000.0
Accordion feature on credit facility			$ 100,000,000.0
Commitment fee percentage (as percent)			0.40%
Remaining borrowing capacity			$ 388,800,000
Maximum borrowing capacity under accordion feature							$ 1,000,000,000.0
Limited guaranty provided by Delek			$ 102,000,000.0
Weighted average interest rate (as percent)			5.10%
Fifth Third Bank | Line of credit | Revolving credit facility | Base Rate | DKL Revolver
Debt Instrument [Line Items]
Description of variable rate basis			U.S. dollar prime rate
Fifth Third Bank | Line of credit | Revolving credit facility | Canadian Prime Rate | DKL Revolver
Debt Instrument [Line Items]
Description of variable rate basis			Canadian prime rate
Fifth Third Bank | Line of credit | Revolving credit facility | London Interbank Offered Rate (LIBOR) | DKL Revolver
Debt Instrument [Line Items]
Description of variable rate basis			LIBOR
Maximum | Line of credit | Revolving credit facility
Debt Instrument [Line Items]
Commitment fee percentage (as percent)		0.375%	0.375%
Maximum | Line of credit | Revolving credit facility | Base Rate
Debt Instrument [Line Items]
Basis spread (as percent)			0.75%
Maximum | Line of credit | Revolving credit facility | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread (as percent)			1.75%
Maximum | Term loan
Debt Instrument [Line Items]
Debt Insrument, Covenant, Prepayment As A Variable Percentage Of Excess Cash Flow		0.00%							0.00%
Minimum | Line of credit | Revolving credit facility
Debt Instrument [Line Items]
Commitment fee percentage (as percent)		0.25%
Minimum | Term loan
Debt Instrument [Line Items]
Debt Insrument, Covenant, Prepayment As A Variable Percentage Of Excess Cash Flow		50.00%							50.00%
Minimum | Term loan | Base Rate
Debt Instrument [Line Items]
Basis spread (as percent)	1.25%
Minimum | Term loan | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread (as percent)	2.25%

[1] Income tax benefit for the quarter ended March 31, 2018 reflects a correction made in our 2018 Annual Report on Form 10-K (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 March 31, 2018 Quarterly Report on Form 10-Q filed on May 10, 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 filed on March 1, 2019 for further discussion.