INVESTMENTS IN DEBT SECURITIES - Short-Term and Long-Term Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 626,241
Fair Value	628,455
Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	354,234	$ 402,814
Gross Unrealized Gains	616	713
Gross Unrealized Losses	(9)	(101)
Fair Value	354,841	403,426
Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	272,007	470,808
Gross Unrealized Gains	1,821	1,938
Gross Unrealized Losses	(214)	(769)
Fair Value	273,614	471,977
U.S. agency securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	31,999	34,454
Gross Unrealized Gains	1	15
Gross Unrealized Losses	(4)	(1)
Fair Value	31,996	34,468
U.S. agency securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	39,017	49,017
Gross Unrealized Gains	64	23
Gross Unrealized Losses	0	(10)
Fair Value	39,081	49,030
Corporate bonds \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	99,096	160,238
Gross Unrealized Gains	191	248
Gross Unrealized Losses	(4)	(96)
Fair Value	99,283	160,390
Corporate bonds \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	72,364	195,035
Gross Unrealized Gains	340	693
Gross Unrealized Losses	(27)	(384)
Fair Value	72,677	195,344
Commercial paper \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	585	333
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	585	333
Municipal securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	305	398
Gross Unrealized Gains	0	1
Gross Unrealized Losses	0	0
Fair Value	305	399
Municipal securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,445	4,592
Gross Unrealized Gains	29	4
Gross Unrealized Losses	(161)	(251)
Fair Value	4,313	4,345
Certificates of deposit \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,188	1,051
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	1,188	1,051
U.S. government securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	221,061	206,340
Gross Unrealized Gains	424	449
Gross Unrealized Losses	(1)	(4)
Fair Value	221,484	206,785
U.S. government securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	156,181	222,164
Gross Unrealized Gains	1,388	1,218
Gross Unrealized Losses	(26)	(124)
Fair Value	$ 157,543	$ 223,258

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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