STOCKHOLDERS' EQUITY AND LOSS PER SHARE (Details) $ / shares in Units, $ in Thousands				3 Months Ended		12 Months Ended
	Feb. 11, 2020 USD ($) shares	Feb. 10, 2020 shares	Feb. 06, 2020 $ / shares shares	Mar. 31, 2021 USD ($) vote $ / shares shares	Mar. 31, 2020 USD ($) shares	Dec. 31, 2020 USD ($) $ / shares shares	Aug. 14, 2020 USD ($) $ / shares
Class of Stock [Line Items]
Common stock, shares authorized (in shares)				100,000,000		100,000,000
Number of votes | vote				1
New shares issued (in shares)	201,000
Common stock, par value (in dollars per share) | $ / shares				$ 0.001		$ 0.001
Net proceeds from units issued in the period | $	$ 28,800			$ 4,094	$ 26,460
Gross proceeds from the sale of common stock | $	$ 26,400			$ 4,220	$ 28,750
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)				5,299,703	7,113,091
Principal Owner
Class of Stock [Line Items]
New shares issued (in shares)	134,000
Common stock warrants
Loss Per Share
Total shares excluded from net loss per share attributable to common stockholders (in shares)				0	2,134,362
Common stock options
Loss Per Share
Total shares excluded from net loss per share attributable to common stockholders (in shares)				1,036,358	1,216,765
Number of Restricted Share Units
Loss Per Share
Total shares excluded from net loss per share attributable to common stockholders (in shares)				4,263,345	3,761,964
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) | $ / shares			$ 0.001
Share price (in dollars per share) | $ / shares			$ 1.50
Over-Allotment Option
Class of Stock [Line Items]
New shares issued (in shares)	2,500,000
Over-Allotment Option | Common stock options
Class of Stock [Line Items]
New shares issued (in shares)		2,500,000
Option to purchase period		30 days
At-The-Market Equity Offering
Class of Stock [Line Items]
New shares issued (in shares)				773,900		4,609,701
Common stock, par value (in dollars per share) | $ / shares							$ 0.001
Share price (in dollars per share) | $ / shares				$ 5.45		$ 2.48
Net proceeds from units issued in the period | $				$ 4,200		$ 11,400
Gross proceeds from the sale of common stock | $				4,100		$ 11,000
Sale of stock, authorized amount | $							$ 25,000
Remaining authorized amount to be sold | $				9,400
Universal Shelf Registration
Class of Stock [Line Items]
Sale of stock, authorized amount | $				$ 100,000