CASH, CASH EQUIVALENTS AND INVESTMENTS - Schedule of Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	$ 326,205	$ 351,299
Available-for-sale Securities, Gross Unrealized Gains	0	3
Available-for-sale Securities, Gross Unrealized Losses	(1,150)	(108)
Available-for-sale Securities, Fair Value Disclosure	325,055	351,194
Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	159,732	159,692
Available-for-sale Securities, Gross Unrealized Gains	0	10
Available-for-sale Securities, Gross Unrealized Losses	(4,110)	(134)
Available-for-sale Securities, Fair Value Disclosure	155,622	159,568
Certificates of Deposit [Member] \| Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis		240
Available-for-sale Securities, Gross Unrealized Gains		0
Available-for-sale Securities, Gross Unrealized Losses		0
Available-for-sale Securities, Fair Value Disclosure		240
Corporate Bonds [Member] \| Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	201,492	226,448
Available-for-sale Securities, Gross Unrealized Gains	0	3
Available-for-sale Securities, Gross Unrealized Losses	(469)	(97)
Available-for-sale Securities, Fair Value Disclosure	201,023	226,354
U.S. Government Bonds [Member] \| Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	124,713	124,611
Available-for-sale Securities, Gross Unrealized Gains	0	0
Available-for-sale Securities, Gross Unrealized Losses	(681)	(11)
Available-for-sale Securities, Fair Value Disclosure	124,032	124,600
U.S. Government Bonds [Member] \| Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	159,732	159,692
Available-for-sale Securities, Gross Unrealized Gains	0	10
Available-for-sale Securities, Gross Unrealized Losses	(4,110)	(134)
Available-for-sale Securities, Fair Value Disclosure	$ 155,622	$ 159,568

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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