INVESTMENTS IN DEBT SECURITIES - Debt Securities, Available-for-sale, Unrealized Loss Position, Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Short-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	$ 151,548	$ 190,928
Less than 12 Months, Gross Unrealized Losses	(183)	(1,299)
Greater than 12 months, Fair Value	385,780	813,607
Greater than 12 months, Gross Unrealized Losses	(7,419)	(17,679)
Total, Fair Value	537,328	1,004,535
Total, Gross Unrealized Losses	(7,602)	(18,978)
Long-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	41,269	100,235
Less than 12 Months, Gross Unrealized Losses	(92)	(905)
Greater than 12 months, Fair Value	2,657	471,619
Greater than 12 months, Gross Unrealized Losses	(126)	(25,980)
Total, Fair Value	43,926	571,854
Total, Gross Unrealized Losses	(218)	(26,885)
U.S. agency securities \| Short-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	9,770	8,572
Less than 12 Months, Gross Unrealized Losses	(10)	(24)
Greater than 12 months, Fair Value	57,745	84,628
Greater than 12 months, Gross Unrealized Losses	(1,253)	(2,096)
Total, Fair Value	67,515	93,200
Total, Gross Unrealized Losses	(1,263)	(2,120)
U.S. agency securities \| Long-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value		11,501
Less than 12 Months, Gross Unrealized Losses		(20)
Greater than 12 months, Fair Value		58,814
Greater than 12 months, Gross Unrealized Losses		(3,762)
Total, Fair Value		70,315
Total, Gross Unrealized Losses		(3,782)
Corporate bonds \| Short-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	61,054	34,795
Less than 12 Months, Gross Unrealized Losses	(60)	(423)
Greater than 12 months, Fair Value	110,706	320,748
Greater than 12 months, Gross Unrealized Losses	(1,673)	(7,052)
Total, Fair Value	171,760	355,543
Total, Gross Unrealized Losses	(1,733)	(7,475)
Corporate bonds \| Long-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	11,819	33,862
Less than 12 Months, Gross Unrealized Losses	(31)	(262)
Greater than 12 months, Fair Value	2,274	201,791
Greater than 12 months, Gross Unrealized Losses	(14)	(8,909)
Total, Fair Value	14,093	235,653
Total, Gross Unrealized Losses	(45)	(9,171)
Municipal securities \| Short-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	0	587
Less than 12 Months, Gross Unrealized Losses	0	(13)
Greater than 12 months, Fair Value	9,165	5,811
Greater than 12 months, Gross Unrealized Losses	(231)	(178)
Total, Fair Value	9,165	6,398
Total, Gross Unrealized Losses	(231)	(191)
Municipal securities \| Long-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	976	467
Less than 12 Months, Gross Unrealized Losses	(24)	(33)
Greater than 12 months, Fair Value	383	8,784
Greater than 12 months, Gross Unrealized Losses	(112)	(631)
Total, Fair Value	1,359	9,251
Total, Gross Unrealized Losses	(136)	(664)
U.S. government securities \| Short-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	80,724	146,974
Less than 12 Months, Gross Unrealized Losses	(113)	(839)
Greater than 12 months, Fair Value	207,183	394,880
Greater than 12 months, Gross Unrealized Losses	(4,243)	(8,098)
Total, Fair Value	287,907	541,854
Total, Gross Unrealized Losses	(4,356)	(8,937)
U.S. government securities \| Long-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	28,474	54,405
Less than 12 Months, Gross Unrealized Losses	(37)	(590)
Greater than 12 months, Fair Value	0	201,288
Greater than 12 months, Gross Unrealized Losses	0	(12,620)
Total, Fair Value	28,474	255,693
Total, Gross Unrealized Losses	(37)	(13,210)
Foreign government securities \| Short-term debt 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	981	7,540
Greater than 12 months, Gross Unrealized Losses	(19)	(255)
Total, Fair Value	981	7,540
Total, Gross Unrealized Losses	$ (19)	(255)
Foreign government securities \| Long-term debt securities:
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value		0
Less than 12 Months, Gross Unrealized Losses		0
Greater than 12 months, Fair Value		942
Greater than 12 months, Gross Unrealized Losses		(58)
Total, Fair Value		942
Total, Gross Unrealized Losses		$ (58)

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