INVESTMENTS IN DEBT SECURITIES - Short-Term and Long-Term Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,108,806
Fair Value	1,103,028
Short-term debt securities:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	859,198	$ 1,100,805
Gross Unrealized Gains	306	24
Gross Unrealized Losses	(7,603)	(18,978)
Fair Value	851,901	1,081,851
Short-term debt securities: \| U.S. agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	68,778	96,545
Gross Unrealized Gains	0	16
Gross Unrealized Losses	(1,263)	(2,120)
Fair Value	67,515	94,441
Short-term debt securities: \| Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	216,864	368,110
Gross Unrealized Gains	96	2
Gross Unrealized Losses	(1,733)	(7,475)
Fair Value	215,227	360,637
Short-term debt securities: \| Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	15,159	31,503
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	15,159	31,503
Short-term debt securities: \| Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,396	9,884
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(231)	(191)
Fair Value	9,165	9,693
Short-term debt securities: \| Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,856	6,400
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	3,856	6,400
Short-term debt securities: \| U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	544,145	580,568
Gross Unrealized Gains	210	6
Gross Unrealized Losses	(4,357)	(8,937)
Fair Value	539,998	571,637
Short-term debt securities: \| Foreign government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,000	7,795
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(19)	(255)
Fair Value	981	7,540
Long-term debt securities:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	249,608	600,305
Gross Unrealized Gains	1,739	9
Gross Unrealized Losses	(220)	(26,885)
Fair Value	251,127	573,429
Long-term debt securities: \| U.S. agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		74,097
Gross Unrealized Gains		0
Gross Unrealized Losses		(3,782)
Fair Value		70,315
Long-term debt securities: \| Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	94,564	245,891
Gross Unrealized Gains	809	6
Gross Unrealized Losses	(45)	(9,171)
Fair Value	95,328	236,726
Long-term debt securities: \| Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,495	10,415
Gross Unrealized Gains	55	3
Gross Unrealized Losses	(138)	(664)
Fair Value	2,412	9,754
Long-term debt securities: \| U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	152,549	268,902
Gross Unrealized Gains	875	0
Gross Unrealized Losses	(37)	(13,210)
Fair Value	$ 153,387	255,692
Long-term debt securities: \| Foreign government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		1,000
Gross Unrealized Gains		0
Gross Unrealized Losses		(58)
Fair Value		$ 942

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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