ORGANIZATION AND BUSINESS (Details) - USD ($)			3 Months Ended
	Mar. 03, 2020	Mar. 29, 2019	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Sep. 20, 2016	Sep. 24, 2015
Debt Instrument [Line Items]
Accumulated deficit			$ 349,250,000		$ 346,827,000
Net cash used in operating activities			2,810,000	$ 5,969,000
Cash and cash equivalents			1,617,000		$ 272,000
Working capital			$ 28,800,000
Loans Payable
Debt Instrument [Line Items]
Aggregate principal amount						$ 35,500,000	$ 27,500,000
Aspire Capital Fund, LLC
Debt Instrument [Line Items]
Number of shares issued (in shares)			15,018,729
Consideration received on sale of stock			$ 4,600,000
Common Stock | 2019 Aspire Purchase Agreement
Debt Instrument [Line Items]
Period of purchase stock		30 months
Private Placement | Aspire Capital Fund, LLC
Debt Instrument [Line Items]
Purchase amount of shares authorized	$ 30,000,000.0	$ 30,000,000.0
Number of shares issued (in shares)			11,007,726
Private Placement | Common Stock | Aspire Capital Fund, LLC
Debt Instrument [Line Items]
Period of purchase stock	30 months