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STOCKHOLDERS' EQUITY AND LOSS PER SHARE (Details) - USD ($)						3 Months Ended		6 Months Ended
	Feb. 11, 2020	Feb. 10, 2020	Feb. 06, 2020	Aug. 09, 2019	Jul. 31, 2019	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Class of Stock [Line Items]
Common stock, shares authorized (in shares)								100,000,000		100,000,000
New shares issued (in shares)					3,960,560		2,766,798
Common stock, par value (in dollars per share)								$ 0.001		$ 0.001
Share price (in dollars per share)					$ 2.53
Net proceeds from the sale of common stock from underwritten public offering					$ 9,900,000			$ 26,410,000	$ 0
Net proceeds from units issued in the period	$ 28,800,000			$ 3,000,000	$ 10,000,000	$ 26,460,000
Shares, outstanding (in shares)				1,193,762
Gross proceeds from the second closing							$ 7,000,000
Consideration received from sale of stock								$ 28,800,000
Preferred stock, shares authorized (in shares)								3,000,000		3,000,000
Loss Per Share
Total shares excluded from net loss per share attributable to common stockholders (in shares)								6,885,893	6,266,706
Common stock warrants
Loss Per Share
Total shares excluded from net loss per share attributable to common stockholders (in shares)								2,065,165	2,256,537
Common stock options
Loss Per Share
Total shares excluded from net loss per share attributable to common stockholders (in shares)								1,174,760	1,356,028
Non-vested restricted stock unit awards
Loss Per Share
Total shares excluded from net loss per share attributable to common stockholders (in shares)								3,645,968	2,654,141
Underwritten Public Offering
Class of Stock [Line Items]
New shares issued (in shares)	19,166,667		16,666,667
Common stock, par value (in dollars per share)			$ 0.001
Share price (in dollars per share)			$ 1.50
Shelf registration statement, maximum aggregate proceeds								$ 50,000,000.0
Number of shares issued (in shares)								19,166,667
Remaining amount available								$ 21,200,000
Over-Allotment Option
Class of Stock [Line Items]
New shares issued (in shares)	2,500,000	2,500,000