FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		$ 49,995
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Fair Value		49,995
Treasury discount notes
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		49,995
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Fair Value	$ 0	$ 49,995

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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