SHARE PURCHASE AND SUBSCRIPTION AGREEMENTS - Heartland Share Purchase and Subscription Agreement (Details)		3 Months Ended		9 Months Ended
	Jan. 17, 2020 USD ($) member $ / shares shares	Mar. 31, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2019
Class of Stock
Adjustment of carrying mount of non-controlling interest | $		$ 9,091,068	$ 970,809	$ 9,091,068
Common Class A
Class of Stock
Capital investment, percentage (as a percent)	50.00%
Heartland SPV
Class of Stock
Ownership percentage (as a percent)				35.00%
Number of managers | member	5
Conversion basis ratio (in shares)	1
Annual return (as a percent)				22.50%
Vertex Refining OH, LLC
Class of Stock
Ownership percentage (as a percent)					100.00%
Tensile-Heartland | Preferred Class A
Class of Stock
Preferred stock, dividend percentage (as a percent)	22.50%
Tensile-Heartland | Heartland SPV
Class of Stock
Ownership percentage (as a percent)	65.00%
Number of managers | member	3
Tensile-Heartland | Heartland SPV | Preferred Class A
Class of Stock
Ownership percentage (as a percent)	100.00%
Vertex Operating | Heartland SPV
Class of Stock
Ownership percentage (as a percent)	35.00%
Number of managers | member	2
Heartland SPV
Class of Stock
Purchase amount | $	$ 7,500,000
Percentage acquired (as a percent)	50.00%
Heartland SPV | Common Class A
Class of Stock
Redemption period	180 days
Redemption price, percentage (as a percent)	25.00%
Percentage of aggregate capital investment to be added to original per-unit price to determine cash purchase price (as a percent)	50.00%
Aggregate unpaid annual return | $	$ 21,000,000
Heartland SPV | Tensile-Heartland | Class A-2 Preferred Units
Class of Stock
Share price (in usd per share) | $ / shares	$ 1,000
Additional consideration (in shares)	7,000
Vertex Refining OH, LLC | Heartland SPV | Common Class A
Class of Stock
Consideration transferred (in shares)	13,500
Vertex Refining OH, LLC | Heartland SPV | A-1 Preferred Units
Class of Stock
Consideration transferred (in shares)	13,500
Vertex Refining OH, LLC | Heartland SPV | Common Class B
Class of Stock
Consideration transferred (in shares)	11,300
Vertex Splitter Corporation | Vertex Refining OH, LLC | Heartland SPV | Common Class B
Class of Stock
Consideration transferred (in shares)	248
Vertex Operating | MG SPV | Common Class A
Class of Stock
Consideration transferred (in shares)	1,000
Share price (in usd per share) | $ / shares	$ 1,000
Equity interest issued or issuable | $	$ 1,000,000
Vertex Operating | Heartland SPV | Tensile-Heartland | Common Class A
Class of Stock
Consideration transferred (in shares)	13,500
Total purchase price | $	$ 13,500,000
Vertex Operating | Heartland SPV | Tensile-Heartland | A-1 Preferred Units
Class of Stock
Consideration transferred (in shares)	13,500
Heartland SPV | Heartland SPV | Tensile-Heartland | Common Class A
Class of Stock
Consideration transferred (in shares)	7,500
Total purchase price | $	$ 7,500,000
Heartland SPV | Heartland SPV | Tensile-Heartland | A-1 Preferred Units
Class of Stock
Consideration transferred (in shares)	7,500
MG SPV | Tensile-MG
Class of Stock
Ownership interest (as a percent)	15.00%
MG SPV | Vertex Operating
Class of Stock
Ownership interest (as a percent)	85.00%