SHAREHOLDERS' EQUITY - Dividend Equivalent Liability (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Stockholders' Equity Note [Abstract]
Short-term	$ 212	$ 437
Long-term	101	477
Total	$ 313	$ 914

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Publisher FASB
-Name Accounting Standards Codification
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