FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Included in cash and cash equivalents:
Amortized Cost	$ 16,815	$ 39,771
Estimated Fair Value	16,815	39,771
Restricted cash:
Amortized Cost	1,115	364
Estimated Fair Value	1,115	364
Marketable securities:
Amortized Cost	306,784	116,142
Gross Unrealized Gains	402	6
Gross Unrealized Losses	(212)	(247)
Estimated Fair Value	306,974	115,901
Money market funds
Included in cash and cash equivalents:
Amortized Cost	16,815	39,771
Estimated Fair Value	16,815	39,771
Restricted cash:
Amortized Cost	843	93
Estimated Fair Value	843	93
Certificate of deposit
Restricted cash:
Amortized Cost	272	271
Estimated Fair Value	272	271
U.S. Treasury securities (due in less than one year)
Marketable securities:
Amortized Cost	26,752	12,983
Gross Unrealized Gains	95
Gross Unrealized Losses		(62)
Estimated Fair Value	26,847	12,921
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
Municipal securities (due in one to two years)
Marketable securities:
Amortized Cost		3,000
Gross Unrealized Losses		(24)
Estimated Fair Value		2,976
Government-sponsored enterprise securities (due in less than one year)
Marketable securities:
Amortized Cost	86,250	9,860
Gross Unrealized Gains	43
Gross Unrealized Losses	(92)	(14)
Estimated Fair Value	86,201	9,846
Government-sponsored enterprise securities (due in one to two years)
Marketable securities:
Amortized Cost	13,598
Gross Unrealized Gains	72
Estimated Fair Value	13,670
Commercial paper (due in less than one year)
Marketable securities:
Amortized Cost	102,270	64,285
Gross Unrealized Gains	31	6
Gross Unrealized Losses	(33)	(92)
Estimated Fair Value	102,268	64,199
Corporate notes (due in less than one year)
Marketable securities:
Amortized Cost	48,409	26,014
Gross Unrealized Gains	14
Gross Unrealized Losses	(63)	(55)
Estimated Fair Value	48,360	$ 25,959
Corporate notes (due in one to two years)
Marketable securities:
Amortized Cost	26,628
Gross Unrealized Gains	130
Gross Unrealized Losses	(24)
Estimated Fair Value	$ 26,734

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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