INTANGIBLE ASSETS, NET, AND GOODWILL - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 2,690	$ 2,075
Write-off of abandoned patents	383	145
Amortization of intangible assets	96	115
Patents
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 2,399	1,801
Patents \| Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life	12 years
Patents \| Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life	20 years
Other
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 291	$ 274
Useful life	10 years
STI \| Patents
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 216
STI \| Patents \| Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life	1 year
STI \| Patents \| Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life	10 years
GVR Trade S.A. \| Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life	1 year
GVR Trade S.A. \| Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life	5 years

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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