COMMITMENTS AND CONTINGENCIES - Narrative (Details)		1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 17, 2020 USD ($)	Jun. 30, 2020 USD ($) ft² renewal_term	Jun. 30, 2020 USD ($) ft² renewal_term	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) ft² renewal_term	Jun. 30, 2019 USD ($)
Loss Contingencies [Line Items]
Lease term		5 years	5 years		5 years
Number of additional terms | renewal_term		2	2		2
Renewal term		3 years	3 years		3 years
Area of leased property | ft²		3,038	3,038		3,038
Monthly payment, initial year		$ 4,430	$ 4,430		$ 4,430
Annual payment percentage increase		3.50%	3.50%		3.50%
Monthly fees		$ 2,160	$ 2,160		$ 2,160
Discount rate		12.00%	12.00%		12.00%
Expected remaining term		2 years 9 months 18 days	2 years 9 months 18 days		2 years 9 months 18 days
Amortization of operating lease right-of-use asset			$ 19,000		$ 37,000
Remaining lease term					1 year 3 months 18 days
Lease expense			18,000	$ 32,000	$ 41,000	$ 60,000
Research and development			2,712,000	$ 4,229,000	$ 5,376,000	$ 10,248,000
Bodor Laboratories, Inc.
Loss Contingencies [Line Items]
Non-refundable upfront fees	$ 1,000,000.0
Cash payment	1,800,000
Payments for additional product approval	100,000
Value of shares issued in agreement	1,500,000
Milestone payment	$ 500,000
Research and development		$ 1,000,000.0	$ 1,500,000