Equity-Based Compensation (Details) - Delek US 2006 and 2016 Long-Term Incentive Plan - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized equity-based compensation	$ 51.3		$ 51.3
Weighted-average period for amortization of unrecognized compensation cost			2 years 3 months 18 days
Shares issued (in shares)	78,695	90,552	462,318	535,613
Shares withheld (in shares)	146,148	146,193	470,232	980,954
General and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense	$ 7.3	$ 5.4	$ 18.7	$ 15.6
Equity-based compensation expense, net of tax	$ 5.8	$ 4.3	$ 14.8	$ 12.3

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- 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.

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

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Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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