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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Narrative) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Finance lease assets	$ 508		$ 204
Amounts reclassified to finance lease right-of-use assets	321
Amounts reclassified to operating lease right-of-use assets	$ 0	$ 0
Securities not included in the computation of diluted net loss per share	2,311,399	1,815,502
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	1,361,998	791,233
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	831,901	906,769
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
Right of Use Asset \| Reclassified to finance lease right of use assets [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Finance lease assets			29
Right of Use Asset \| Maximum \| Reclassified to finance lease right of use assets [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Finance lease assets			100
Property, Plant and Equipment [Member] \| Reclassified to finance lease right of use assets [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Finance lease assets			$ 175