INVESTMENTS - By type (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Marketable securities by type
Cost	$ 11,988	$ 27,042
Gross Unrealized Gains	8	1
Gross Unrealized Losses	(2)	(108)
Estimated Fair Value	11,994	26,935
U.S. government agency debt securities
Marketable securities by type
Cost	11,988	27,042
Gross Unrealized Gains	8	1
Gross Unrealized Losses	(2)	(108)
Estimated Fair Value	$ 11,994	$ 26,935

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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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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