SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)		12 Months Ended
	Jul. 25, 2019 USD ($)	Dec. 31, 2019 USD ($) a	Dec. 31, 2018 USD ($)	Jan. 17, 2020	Jan. 01, 2020	Jan. 01, 2019 USD ($)	Nov. 30, 2018 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Liquid storage facility, number of acres | a		19
Restricted cash in money market account		$ 100,170	$ 1,600,000
Collateral for line of credit							$ 1,500,000
Allowance for doubtful accounts		402,475	831,768
Impairment of goodwill		0	176,349
Impairment of long-lived assets		0	$ 0
Payment related to proceeds of an insurance settlement		907,500
Accounting Standards Update 2018-11
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease assets		37,800,000				$ 37,800,000
Accounting Standards Update 2018-15
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Capitalized implementation costs		700,000
Money Market Funds
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash in money market account		$ 100,000
Common Class B | Tensile-Myrtle Grove Acquisition Corporation
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of aggregate capital investment to be added to original per-unit price to determine cash purchase price	50.00%
Percentage of aggregate unpaid annual return	22.50%
Aggregate unpaid annual return	$ 3,000,000
Heartland SPV | Subsequent Event | Tensile-Heartland
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Ownership percentage				65.00%	65.00%
Heartland SPV | Subsequent Event | Vertex Operating
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Ownership percentage				35.00%
MG SPV | Vertex Operating
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Ownership percentage		84.42%