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FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Included in cash and cash equivalents:
Amortized Cost	$ 74,801	$ 16,815
Estimated Fair Value	74,801	16,815
Restricted cash:
Amortized Cost	1,123	1,115
Estimated Fair Value	1,123	1,115
Marketable securities:
Amortized Cost	312,794	306,784
Gross Unrealized Gains	11	402
Gross Unrealized Losses	(511)	(212)
Estimated Fair Value	312,294	306,974
Money market funds
Included in cash and cash equivalents:
Amortized Cost	74,801	16,815
Estimated Fair Value	74,801	16,815
Restricted cash:
Amortized Cost	850	843
Estimated Fair Value	850	843
Certificate of deposit
Restricted cash:
Amortized Cost	273	272
Estimated Fair Value	273	272
U.S. Treasury securities (due in less than one year)
Marketable securities:
Amortized Cost	39,885	26,752
Gross Unrealized Gains		95
Gross Unrealized Losses	(30)
Estimated Fair Value	39,855	26,847
U.S. Treasury securities (due in one to two years)
Marketable securities:
Amortized Cost		2,877
Gross Unrealized Gains		17
Estimated Fair Value		2,894
Government-sponsored enterprise securities (due in less than one year)
Marketable securities:
Amortized Cost	44,532	86,250
Gross Unrealized Gains	2	43
Gross Unrealized Losses	(44)	(92)
Estimated Fair Value	44,490	86,201
Government-sponsored enterprise securities (due in one to two years)
Marketable securities:
Amortized Cost	5,000	13,598
Gross Unrealized Gains		72
Gross Unrealized Losses	(9)
Estimated Fair Value	4,991	13,670
Commercial paper (due in less than one year)
Marketable securities:
Amortized Cost	110,400	102,270
Gross Unrealized Gains	1	31
Gross Unrealized Losses	(192)	(33)
Estimated Fair Value	110,209	102,268
Corporate notes (due in less than one year)
Marketable securities:
Amortized Cost	51,347	48,409
Gross Unrealized Gains	3	14
Gross Unrealized Losses	(115)	(63)
Estimated Fair Value	51,235	48,360
Corporate notes (due in one to two years)
Marketable securities:
Amortized Cost	61,630	26,628
Gross Unrealized Gains	5	130
Gross Unrealized Losses	(121)	(24)
Estimated Fair Value	$ 61,514	$ 26,734

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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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