INVESTMENTS IN DEBT SECURITIES - Short-Term and Long-Term Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 546,283
Fair Value	547,556
Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	370,004	$ 402,814
Gross Unrealized Gains	813	713
Gross Unrealized Losses	(45)	(101)
Fair Value	370,772	403,426
Short-term debt securities \| U.S. agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	24,017	34,454
Gross Unrealized Gains	12	15
Gross Unrealized Losses	0	(1)
Fair Value	24,029	34,468
Short-term debt securities \| Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	65,035	160,238
Gross Unrealized Gains	201	248
Gross Unrealized Losses	(5)	(96)
Fair Value	65,231	160,390
Short-term debt securities \| Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	8,418	333
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	8,418	333
Short-term debt securities \| Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	130	398
Gross Unrealized Gains	1	1
Gross Unrealized Losses	0	0
Fair Value	131	399
Short-term debt securities \| Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,246	1,051
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	1,246	1,051
Short-term debt securities \| U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	271,158	206,340
Gross Unrealized Gains	599	449
Gross Unrealized Losses	(40)	(4)
Fair Value	271,717	206,785
Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	176,279	470,808
Gross Unrealized Gains	684	1,938
Gross Unrealized Losses	(179)	(769)
Fair Value	176,784	471,977
Long-term debt securities \| U.S. agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	5,000	49,017
Gross Unrealized Gains	5	23
Gross Unrealized Losses	0	(10)
Fair Value	5,005	49,030
Long-term debt securities \| Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	47,448	195,035
Gross Unrealized Gains	111	693
Gross Unrealized Losses	(2)	(384)
Fair Value	47,557	195,344
Long-term debt securities \| Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	5,667	4,592
Gross Unrealized Gains	47	4
Gross Unrealized Losses	(171)	(251)
Fair Value	5,543	4,345
Long-term debt securities \| U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	118,164	222,164
Gross Unrealized Gains	521	1,218
Gross Unrealized Losses	(6)	(124)
Fair Value	$ 118,679	$ 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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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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