INVESTMENTS IN DEBT SECURITIES - Short-Term and Long-Term Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,021,375
Fair Value	1,019,758
Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	659,416	$ 859,198
Gross Unrealized Gains	49	306
Gross Unrealized Losses	(1,464)	(7,603)
Fair Value	658,001	851,901
Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	361,959	249,608
Gross Unrealized Gains	389	1,739
Gross Unrealized Losses	(591)	(220)
Fair Value	361,757	251,127
U.S. agency securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	38,887	68,778
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(167)	(1,263)
Fair Value	38,720	67,515
U.S. agency securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	17
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair Value	17
Corporate bonds \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	119,358	216,864
Gross Unrealized Gains	40	96
Gross Unrealized Losses	(273)	(1,733)
Fair Value	119,125	215,227
Corporate bonds \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	142,220	94,564
Gross Unrealized Gains	126	809
Gross Unrealized Losses	(328)	(45)
Fair Value	142,018	95,328
Commercial paper \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,255	15,159
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	1,255	15,159
Municipal securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,478	9,396
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(30)	(231)
Fair Value	9,448	9,165
Municipal securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,480	2,495
Gross Unrealized Gains	18	55
Gross Unrealized Losses	(175)	(138)
Fair Value	3,323	2,412
Certificates of deposit \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,238	3,856
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	1,238	3,856
U.S. government securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	489,200	544,145
Gross Unrealized Gains	9	210
Gross Unrealized Losses	(994)	(4,357)
Fair Value	488,215	539,998
U.S. government securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	216,242	152,549
Gross Unrealized Gains	245	875
Gross Unrealized Losses	(88)	(37)
Fair Value	$ 216,399	153,387
Foreign government securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		1,000
Gross Unrealized Gains		0
Gross Unrealized Losses		(19)
Fair Value		$ 981

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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