WARRANTS (Warrant Share Activity) (Details) - $ / shares	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Common stock warrants
Roll forward of warrant activity
Balance at the beginning of the period (in warrants)	3,385,100	3,730,255
Warrants exercised/expired (in warrants)	(1,128,563)	(339,155)
Balance at the end of the period (in warrants)	2,256,537	3,391,100
Bridge Warrants | Common stock warrants
Roll forward of warrant activity
Balance at the beginning of the period (in warrants)		249,999
Warrants exercised/expired (in warrants)		(249,999)
Balance at the end of the period (in warrants)		0
Exercise of warrants, net (in shares)		242,913
Consulting Warrants | Common stock warrants
Warrant liabilities
Exercise price (in dollars per share)			$ 0.01
Roll forward of warrant activity
Balance at the beginning of the period (in warrants)	6,667	12,223
Warrants exercised/expired (in warrants)	0	(5,556)
Balance at the end of the period (in warrants)	6,667	6,667
Exercise of warrants, net (in shares)		5,542
Financing Warrants | Common stock warrants
Warrant liabilities
Exercise price (in dollars per share)			3.35
Roll forward of warrant activity
Balance at the beginning of the period (in warrants)	62,530	62,530
Warrants exercised/expired (in warrants)	0	0
Balance at the end of the period (in warrants)	62,530	62,530
Underwriting Warrants | Common stock warrants
Warrant liabilities
Exercise price (in dollars per share)			7.5
Roll forward of warrant activity
Balance at the beginning of the period (in warrants)	310,500	310,500
Warrants exercised/expired (in warrants)	(310,500)	0
Balance at the end of the period (in warrants)	0	310,500
IR Consulting Warrants | Common stock warrants
Roll forward of warrant activity
Balance at the beginning of the period (in warrants)		6,000
Warrants exercised/expired (in warrants)		0
Balance at the end of the period (in warrants)		6,000
Private Placement Warrants - 2016
Roll forward of warrant activity
Warrants exercised/expired (in warrants)	(288,135)	(73,000)
Exercise of warrants (in shares)	485,000
Warrants exercised, cashless exercise (in warrants)	44,928
Exercise of warrants, net (in shares)	1,809
Private Placement Warrants - 2016 | Common stock warrants
Warrant liabilities
Exercise price (in dollars per share)			2.86
Roll forward of warrant activity
Balance at the beginning of the period (in warrants)	818,063	891,063
Warrants exercised/expired (in warrants)	(818,063)	(73,000)
Balance at the end of the period (in warrants)	0	818,063
Underwriting Warrants - Public Offering 2016 | Common stock warrants
Warrant liabilities
Exercise price (in dollars per share)			4.25
Roll forward of warrant activity
Balance at the beginning of the period (in warrants)	122,175	122,175
Warrants exercised/expired (in warrants)	0	0
Balance at the end of the period (in warrants)	122,175	122,175
Private Placement Warrants - September 2017 | Common stock warrants
Warrant liabilities
Exercise price (in dollars per share)			4.85
Roll forward of warrant activity
Balance at the beginning of the period (in warrants)	1,966,319	1,976,919
Warrants exercised/expired (in warrants)	0	(10,600)
Balance at the end of the period (in warrants)	1,966,319	1,966,319
Placement Agent Warrants | Common stock warrants
Warrant liabilities
Exercise price (in dollars per share)			$ 4.85
Roll forward of warrant activity
Balance at the beginning of the period (in warrants)	98,846	98,846
Warrants exercised/expired (in warrants)	0	0
Balance at the end of the period (in warrants)	98,846	98,846