LONG-TERM DEBT - Warrants fair value (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
Amortization of Debt Issuance Costs		$ 694	$ 539
Unamortized Debt Issuance Expense	$ 1,311	$ 1,311
Warrant [Member]
Warrant coverage percentage		2.00%
Warrants issued	147,058	147,058
Warrant, purchase price	$ 4.08	$ 4.08
Class Of Warrant Or Right Fair Value	$ 1,000	$ 1,000
Warrant exercisable term		7 years
Financing expenses, Hercules Loan Agreement		$ 2,800
Amortization of Debt Issuance Costs	200	700
Unamortized Debt Issuance Expense	$ 1,300	$ 1,300

No definition available.

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- Definition

Warrant coverage percentage.

+ References

No definition available.

+ Details

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- Definition

Warrant exercisable term.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Name Accounting Standards Codification
-Topic 220
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

This element represents interest incurred for borrowed money which was used to produce goods or render services.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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