SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Jan. 01, 2020 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash	$ 55,000	$ 0
Deferred offering costs	$ 2,303,000	0
Number of operating segments | segment	1
Other comprehensive income	$ 0	$ 0
Forecast | ASU 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use asset			$ 476,000
Lease liability			$ 480,000