Acquisitions - Components of Consideration Transferred (Details) - Alon $ / shares in Units, $ in Millions	Jul. 01, 2017 USD ($) $ / shares shares
Business Acquisition [Line Items]
Delek common stock issued (in shares) | shares	19,250,795.088
Ending price per share of Delek Common Stock immediately before the Effective Time (in dollars per share) | $ / shares	$ 26.44
Total value of common stock consideration	$ 509.0
Additional consideration	21.7	[1]
Fair value of Delek's pre-existing equity method investment in Alon	449.0	[2]
Consideration transferred	$ 979.7

[1] Additional consideration includes the fair value of certain equity instruments originally indexed to Alon stock that were exchanged for instruments indexed to New Delek's stock, as well as the fair value of certain share-based payments that were required to be exchanged for awards indexed to New Delek's stock in connection with the Delek/Alon Merger.

[2] The fair value of Delek's pre-existing equity method investment in Alon was based on the quoted market price of shares of Alon.