INVESTMENTS IN DEBT SECURITIES - Short-Term and Long-Term Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 931,256
Fair Value	937,162
Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	503,871	$ 859,198
Gross Unrealized Gains	1,250	306
Gross Unrealized Losses	(135)	(7,603)
Fair Value	504,986	851,901
Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	427,385	249,608
Gross Unrealized Gains	4,990	1,739
Gross Unrealized Losses	(199)	(220)
Fair Value	432,176	251,127
U.S. agency securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	33,760	68,778
Gross Unrealized Gains	42	0
Gross Unrealized Losses	(30)	(1,263)
Fair Value	33,772	67,515
U.S. agency securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	39,017
Gross Unrealized Gains	22
Gross Unrealized Losses	(5)
Fair Value	39,034
Corporate bonds \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	136,975	216,864
Gross Unrealized Gains	501	96
Gross Unrealized Losses	(12)	(1,733)
Fair Value	137,464	215,227
Corporate bonds \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	185,156	94,564
Gross Unrealized Gains	1,691	809
Gross Unrealized Losses	(62)	(45)
Fair Value	186,785	95,328
Commercial paper \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	598	15,159
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	598	15,159
Municipal securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	92	9,396
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(231)
Fair Value	92	9,165
Municipal securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,462	2,495
Gross Unrealized Gains	65	55
Gross Unrealized Losses	(128)	(138)
Fair Value	3,399	2,412
Certificates of deposit \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	738	3,856
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	738	3,856
Certificates of deposit \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	515
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair Value	515
U.S. government securities \| Short-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	331,708	544,145
Gross Unrealized Gains	707	210
Gross Unrealized Losses	(93)	(4,357)
Fair Value	332,322	539,998
U.S. government securities \| Long-term debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	199,235	152,549
Gross Unrealized Gains	3,212	875
Gross Unrealized Losses	(4)	(37)
Fair Value	$ 202,443	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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