Contractual interest rate for funds borrowed, under the debt agreement.

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Long-Term Obligations and Notes Payable - Promissory Notes Narrative (Details) - USD ($) $ in Millions	May 14, 2015	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt		$ 2,067.1	$ 1,783.3
Alon USA Energy, Inc. \| Loans Payable \| Unsecured Promissory Note, Alon
Debt Instrument [Line Items]
Interest rate, stated percentage	5.50%
Periodic payment, principal	$ 25.0
Periodic payment terms, balloon payment to be paid	$ 20.0
Long-term debt		$ 45.0