MARKETABLE SECURITIES - Schedule of Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Cost Basis	$ 1,317	$ 4,995
Gross Unrealized Losses	(480)	(543)
Gross Unrealized Gains	701	386
Fair Value	1,538	4,838
Marketable debt securities
Debt Securities, Available-for-sale [Line Items]
Cost Basis	493	4,171
Gross Unrealized Losses	0	0
Gross Unrealized Gains	9	37
Fair Value	502	4,208
Marketable equity securities
Debt Securities, Available-for-sale [Line Items]
Cost Basis	824	824
Gross Unrealized Losses	(480)	(543)
Gross Unrealized Gains	692	349
Fair Value	$ 1,036	$ 630

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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