Summary of Significant Accounting Policies (Details Textual)		3 Months Ended		4 Months Ended
	Jun. 02, 2016 USD ($)	Mar. 31, 2020 USD ($) renewable_identification_number	Mar. 31, 2019 USD ($)	May 01, 2020 USD ($)	Feb. 29, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jan. 31, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2016 USD ($)
Business Acquisition [Line Items]
Restricted cash		$ 3,000,000	$ 3,000,000			$ 3,000,000
Amount of BTC receivables received from the federal government		104,598,000	(30,516,000)
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt, Subsequent Adjustments		17,829,000	152,000
Gain (loss) on debt extinguishment		1,172,000	(2,000)
June 2018 Program
Business Acquisition [Line Items]
Security repurchase program, amount authorized to be repurchased								$ 75,000,000
January 2019 Program
Business Acquisition [Line Items]
Security repurchase program, amount authorized to be repurchased							$ 75,000,000
Security repurchase program, remaining amounts		41,847,000
February 2020 Program
Business Acquisition [Line Items]
Security repurchase program, amount authorized to be repurchased					$ 100,000,000
January 2019 Program and February 2020 Program
Business Acquisition [Line Items]
Security repurchase program, remaining amounts		141,847,000
2036 Senior Convertible Notes Repurchases | Convertible Notes
Business Acquisition [Line Items]
Face amount	$ 152,000,000								$ 152,000,000
Interest rate	4.00%								4.00%
Convertible Notes Repurchases	$ 147,118,000	25,949,000	0
Principal amount of debt repurchased		11,008,000	11,008,000
Gain (loss) on debt extinguishment		$ 1,172,000
2036 Senior Convertible Notes Repurchases | Convertible Notes | January 2019 Program
Business Acquisition [Line Items]
Convertible Notes Repurchases			$ 25,949,000
Minimum
Business Acquisition [Line Items]
RINs per gallon | renewable_identification_number		1.5
Allowed RINs per gallon | renewable_identification_number		0
Maximum
Business Acquisition [Line Items]
RINs per gallon | renewable_identification_number		1.7
Allowed RINs per gallon | renewable_identification_number		2.5
BTC receivables from the government | Subsequent Event
Business Acquisition [Line Items]
Amount of BTC receivables received from the federal government				$ 671,740,000