REVENUES (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Total revenues	$ 36,203,429	$ 39,320,712
Petroleum products
Disaggregation of Revenue [Line Items]
Total revenues	32,794,746	36,885,323
Metals
Disaggregation of Revenue [Line Items]
Total revenues	3,408,683	2,435,389
Northern United States
Disaggregation of Revenue [Line Items]
Total revenues	9,558,568	9,323,782
Southern United States
Disaggregation of Revenue [Line Items]
Total revenues	26,644,861	29,996,930
Black Oil
Disaggregation of Revenue [Line Items]
Total revenues	29,531,370	32,815,187
Black Oil | Petroleum products
Disaggregation of Revenue [Line Items]
Total revenues	29,531,370	32,815,187
Black Oil | Metals
Disaggregation of Revenue [Line Items]
Total revenues	0	0
Black Oil | Northern United States
Disaggregation of Revenue [Line Items]
Total revenues	9,558,568	9,323,782
Black Oil | Southern United States
Disaggregation of Revenue [Line Items]
Total revenues	19,972,802	23,491,405
Refining & Marketing
Disaggregation of Revenue [Line Items]
Total revenues	2,510,593	2,858,621
Refining & Marketing | Petroleum products
Disaggregation of Revenue [Line Items]
Total revenues	2,510,593	2,858,621
Refining & Marketing | Metals
Disaggregation of Revenue [Line Items]
Total revenues	0	0
Refining & Marketing | Northern United States
Disaggregation of Revenue [Line Items]
Total revenues	0	0
Refining & Marketing | Southern United States
Disaggregation of Revenue [Line Items]
Total revenues	2,510,593	2,858,621
Recovery
Disaggregation of Revenue [Line Items]
Total revenues	4,161,466	3,646,904
Recovery | Petroleum products
Disaggregation of Revenue [Line Items]
Total revenues	752,783	1,211,515
Recovery | Metals
Disaggregation of Revenue [Line Items]
Total revenues	3,408,683	2,435,389
Recovery | Northern United States
Disaggregation of Revenue [Line Items]
Total revenues	0	0
Recovery | Southern United States
Disaggregation of Revenue [Line Items]
Total revenues	$ 4,161,466	$ 3,646,904