Maximum Borrowing Capacity under Accordion Feature

No definition available.

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Namespace Prefix:	dk_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Related Party Limiited Guaranty of Debt

+ References

No definition available.

+ Details

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Namespace Prefix:	dk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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Balance Type:
Period Type:

- Details

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Period Type:

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=dk_DklRevolverMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=dk_SecondAmendedandRestatedCreditAgreementMember
Namespace Prefix:
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Long-Term Obligations - Second Amended and Restated Credit Agreement (Details) - Line of Credit - Revolving Credit Facility - Fifth Third Bank - USD ($)		3 Months Ended
	Dec. 30, 2014	Mar. 31, 2019	Dec. 31, 2018	Sep. 28, 2018	Sep. 27, 2018
Line of Credit Facility [Line Items]
Weighted average interest rate (as percent)		5.10%
Prime Rate \| United States of America, Dollars
Line of Credit Facility [Line Items]
Variable rate description	U.S. dollar prime rate
London Interbank Offered Rate (LIBOR) \| United States of America, Dollars
Line of Credit Facility [Line Items]
Variable rate description	LIBOR
Canadian prime rate \| Canada, Dollars
Line of Credit Facility [Line Items]
Variable rate description	Canadian dollar prime rate
Canadian Dealer Offered Rate (CDOR) \| Canada, Dollars
Line of Credit Facility [Line Items]
Variable rate description	Canadian Dealer Offered Rate
DKL Revolver
Line of Credit Facility [Line Items]
Maximum lender commitment				$ 850,000,000.0	$ 700,000,000.0
Maximum amount under accordion feature				$ 1,000,000,000.0
Second Amended and Restated Credit Agreement
Line of Credit Facility [Line Items]
Maximum lender commitment			$ 700,000,000.0
Commitment fee (as percent)		0.40%
Principal amount of Holdings Note		$ 102,000,000.0
Outstanding borrowings		461,200,000
Letters of credit outstanding		0
Unused credit commitment		$ 388,800,000