MARKETABLE SECURITIES - Fair Value, Cost and Gross Unrealized Holding Gains of Securities Owned (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Fair value	$ 2,018	$ 15,660
Cost or amortized cost	2,018	15,656
Gross unrealized holding losses	0	0
Gross unrealized holding gains	0	4
Corporate notes
Debt Securities, Available-for-sale [Line Items]
Fair value	2,018
Cost or amortized cost	2,018
Gross unrealized holding losses	0
Gross unrealized holding gains	$ 0
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Fair value		151
Cost or amortized cost		151
Gross unrealized holding losses		0
Gross unrealized holding gains		0
U.S Government
Debt Securities, Available-for-sale [Line Items]
Fair value		6,031
Cost or amortized cost		6,030
Gross unrealized holding losses		0
Gross unrealized holding gains		1
U.S Treasury bills
Debt Securities, Available-for-sale [Line Items]
Fair value		9,478
Cost or amortized cost		9,475
Gross unrealized holding losses		0
Gross unrealized holding gains		$ 3

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).

+ References

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-Publisher FASB
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Amount 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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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