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SUBSEQUENT EVENTS (Details) - USD ($)				3 Months Ended
	May 27, 2020	Jul. 10, 2018	May 18, 2018	Jun. 30, 2020	Mar. 31, 2020
Subsequent Event [Line Items]
Issuance of common stock in connection with at market offering, net of issuance costs					$ 686,000
Subsequent Event | Underwritten Public Offering
Subsequent Event [Line Items]
Issuance of common stock in connection with public offering (in shares)	107,049,375
Estimated net proceeds from public offering	$ 140,200,000
Combined public offering price per share of common stock and accompanying stock purchase warrants	$ 1.30
Pre-Funded Warrants | Subsequent Event | Underwritten Public Offering
Subsequent Event [Line Items]
Warrants to purchase common stock, shares	8,335,239
Combined public offering price per share of pre-funded warrants and accompanying stock purchase warrants	$ 1.299
Stock Purchase Warrants | Subsequent Event | Underwritten Public Offering
Subsequent Event [Line Items]
Warrants to purchase common stock, shares	57,692,307
2018 Sales Agreement
Subsequent Event [Line Items]
Issuance of common stock in connection with at market offering, net of issuance costs (in shares)					530,228
Issuance of common stock in connection with at market offering, net of issuance costs					$ 686,000
Aggregate offering price of common stock		$ 62,821,700	$ 100,000,000
Forecast | 2018 Sales Agreement
Subsequent Event [Line Items]
Issuance of common stock in connection with at market offering, net of issuance costs (in shares)				2,966,388
Issuance of common stock in connection with at market offering, net of issuance costs				$ 3,391,000

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