MARKETABLE SECURITIES Marketable Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Interest receivable	$ 1,400	$ 1,500
Amortized Cost	266,715	373,400
Gross Unrealized Gains	0	21
Gross Unrealized Losses	(6,506)	(1,186)
Estimated Fair Market Value	260,209	372,235
Investments due in 3 months or less:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	6,316	97,250
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(14)	(3)
Estimated Fair Market Value	6,302	97,247
Investments due in 4-12 months:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	113,048	25,054
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2,253)	(42)
Estimated Fair Market Value	110,795	25,012
Investments due in 12 months or greater:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	147,351	251,096
Gross Unrealized Gains	0	21
Gross Unrealized Losses	(4,239)	(1,141)
Estimated Fair Market Value	143,112	249,976
Commercial paper \| Investments due in 3 months or less:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		89,965
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Market Value		89,965
Corporate securities \| Investments due in 3 months or less:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	6,316	7,285
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(14)	(3)
Estimated Fair Market Value	6,302	7,282
Corporate securities \| Investments due in 4-12 months:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	113,048	25,054
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2,253)	(42)
Estimated Fair Market Value	110,795	25,012
Corporate securities \| Investments due in 12 months or greater:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	147,351	251,096
Gross Unrealized Gains	0	21
Gross Unrealized Losses	(4,239)	(1,141)
Estimated Fair Market Value	$ 143,112	$ 249,976

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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Amount of investment in marketable security.

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