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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Finance lease assets	$ 289		$ 204
Amounts reclassified to finance lease right-of-use assets	96
Amounts reclassified to operating lease right-of-use assets	$ 0	$ 0
Securities not included in the computation of diluted net loss per share	2,381,497	5,859,395
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities not included in the computation of diluted net loss per share	1,358,096	802,113
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities not included in the computation of diluted net loss per share	905,901	907,601
Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities not included in the computation of diluted net loss per share	117,500	117,500
Convertible Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities not included in the computation of diluted net loss per share		4,032,181
Reclassified to finance lease right of use assets [Member] \| Right of Use Asset
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Finance lease assets			29
Reclassified to finance lease right of use assets [Member] \| Property, Plant and Equipment
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Finance lease assets			$ 175