INVESTMENTS IN DEBT SECURITIES - Short-Term and Long-Term Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 764,808
Fair Value	761,312
Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	577,048	$ 859,198
Gross Unrealized Gains	103	306
Gross Unrealized Losses	(3,761)	(7,603)
Fair Value	573,390	851,901
Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	187,760	249,608
Gross Unrealized Gains	454	1,739
Gross Unrealized Losses	(292)	(220)
Fair Value	187,922	251,127
U.S. agency securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	58,399	68,778
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(676)	(1,263)
Fair Value	57,723	67,515
Corporate bonds \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	135,097	216,864
Gross Unrealized Gains	60	96
Gross Unrealized Losses	(626)	(1,733)
Fair Value	134,531	215,227
Corporate bonds \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	96,206	94,564
Gross Unrealized Gains	273	809
Gross Unrealized Losses	(95)	(45)
Fair Value	96,384	95,328
Commercial paper \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	724	15,159
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	724	15,159
Municipal securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,391	9,396
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(138)	(231)
Fair Value	9,253	9,165
Municipal securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,481	2,495
Gross Unrealized Gains	30	55
Gross Unrealized Losses	(119)	(138)
Fair Value	2,392	2,412
Certificates of deposit \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	500	3,856
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	500	3,856
U.S. government securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	372,337	544,145
Gross Unrealized Gains	43	210
Gross Unrealized Losses	(2,317)	(4,357)
Fair Value	370,063	539,998
U.S. government securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	89,073	152,549
Gross Unrealized Gains	151	875
Gross Unrealized Losses	(78)	(37)
Fair Value	89,146	153,387
Foreign government securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	600	1,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(4)	(19)
Fair Value	$ 596	$ 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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