DEBT - Convertible notes (Details) - USD ($)		12 Months Ended
	Oct. 16, 2017	Dec. 31, 2017	Dec. 31, 2016	Jan. 30, 2017
Convertible notes
Loss on conversion of notes payable		$ 1,771,650
Charge to additional paid-in capital for warrants issued		2,978,796	$ 1,033,586
Original Convertible Notes
Convertible notes
Face amount				$ 10,000,000
Interest rate (as a percent)				10.00%
Conversion price (in dollars per share)	$ 1.10			$ 1.50
Net proceeds from private placement		9,000,000
Principal converted	$ 5,200,000
Convertible accrued interest	$ 100,000
Number of shares issued	4,814,265
Loss on conversion of notes payable	$ 1,800,000
Charge to additional paid-in capital for warrants issued		$ 1,000,000