Derivatives - Fair Value Amounts of Derivatives and Placement in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Prepaid and other current assets
Derivative Instruments, Gain (Loss) [Line Items]
Cash collateral	$ 2,700	$ 10,300
Other non-current assets
Derivative Instruments, Gain (Loss) [Line Items]
Cash collateral	9,500	9,500
Commodity derivatives | Prepaid and other current assets
Derivative Instruments, Gain (Loss) [Line Items]
Asset (Liability)	3,177	2,075
Commodity derivatives | Other accrued liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Asset (Liability)	(6,662)	(5,534)
J. Aron repurchase obligation derivative | Over the Counter | Obligations under inventory financing agreements
Derivative Instruments, Gain (Loss) [Line Items]
Asset (Liability)	(56,842)	173
MLC terminal obligation derivative | Over the Counter | Obligations under inventory financing agreements
Derivative Instruments, Gain (Loss) [Line Items]
Asset (Liability)	(9,256)	(14,717)
Interest rate derivatives | Other accrued liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Asset (Liability)	(974)	(314)
Interest rate derivatives | Other liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Asset (Liability)	$ (2,557)	$ (1,113)