INVESTMENTS IN DEBT SECURITIES - Debt Securities, Available-for-sale, Unrealized Loss Position, Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Short-term debt securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	$ 138,148	$ 151,548
Less than 12 Months, Gross Unrealized Losses	(126)	(183)
Greater than 12 months, Fair Value	282,043	385,780
Greater than 12 months, Gross Unrealized Losses	(3,635)	(7,419)
Total, Fair Value	420,191	537,328
Total, Gross Unrealized Losses	(3,761)	(7,602)
Short-term debt securities \| U.S. agency securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	400	9,770
Less than 12 Months, Gross Unrealized Losses	0	(10)
Greater than 12 months, Fair Value	57,322	57,745
Greater than 12 months, Gross Unrealized Losses	(676)	(1,253)
Total, Fair Value	57,722	67,515
Total, Gross Unrealized Losses	(676)	(1,263)
Short-term debt securities \| Corporate bonds
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	44,988	61,054
Less than 12 Months, Gross Unrealized Losses	(48)	(60)
Greater than 12 months, Fair Value	52,483	110,706
Greater than 12 months, Gross Unrealized Losses	(578)	(1,673)
Total, Fair Value	97,471	171,760
Total, Gross Unrealized Losses	(626)	(1,733)
Short-term debt securities \| Municipal securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	0	0
Less than 12 Months, Gross Unrealized Losses	0	0
Greater than 12 months, Fair Value	9,253	9,165
Greater than 12 months, Gross Unrealized Losses	(138)	(231)
Total, Fair Value	9,253	9,165
Total, Gross Unrealized Losses	(138)	(231)
Short-term debt securities \| U.S. government securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	92,760	80,724
Less than 12 Months, Gross Unrealized Losses	(78)	(113)
Greater than 12 months, Fair Value	162,389	207,183
Greater than 12 months, Gross Unrealized Losses	(2,239)	(4,243)
Total, Fair Value	255,149	287,907
Total, Gross Unrealized Losses	(2,317)	(4,356)
Short-term debt securities \| Foreign government securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	0	0
Less than 12 Months, Gross Unrealized Losses	0	0
Greater than 12 months, Fair Value	596	981
Greater than 12 months, Gross Unrealized Losses	(4)	(19)
Total, Fair Value	596	981
Total, Gross Unrealized Losses	(4)	(19)
Long-term debt securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	72,642	41,269
Less than 12 Months, Gross Unrealized Losses	(178)	(92)
Greater than 12 months, Fair Value	1,365	2,657
Greater than 12 months, Gross Unrealized Losses	(114)	(126)
Total, Fair Value	74,007	43,926
Total, Gross Unrealized Losses	(292)	(218)
Long-term debt securities \| Corporate bonds
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	45,907	11,819
Less than 12 Months, Gross Unrealized Losses	(87)	(31)
Greater than 12 months, Fair Value	980	2,274
Greater than 12 months, Gross Unrealized Losses	(8)	(14)
Total, Fair Value	46,887	14,093
Total, Gross Unrealized Losses	(95)	(45)
Long-term debt securities \| Municipal securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	977	976
Less than 12 Months, Gross Unrealized Losses	(13)	(24)
Greater than 12 months, Fair Value	385	383
Greater than 12 months, Gross Unrealized Losses	(106)	(112)
Total, Fair Value	1,362	1,359
Total, Gross Unrealized Losses	(119)	(136)
Long-term debt securities \| U.S. government securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	25,758	28,474
Less than 12 Months, Gross Unrealized Losses	(78)	(37)
Greater than 12 months, Fair Value	0	0
Greater than 12 months, Gross Unrealized Losses	0	0
Total, Fair Value	25,758	28,474
Total, Gross Unrealized Losses	$ (78)	$ (37)

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