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FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Included in cash and cash equivalents:
Amortized Cost	$ 148,743	$ 16,815
Estimated Fair Value	148,743	16,815
Restricted cash:
Amortized Cost	1,119	1,115
Estimated Fair Value	1,119	1,115
Marketable securities:
Amortized Cost	274,330	306,784
Gross Unrealized Gains	54	402
Gross Unrealized Losses	(314)	(212)
Estimated Fair Value	274,070	306,974
Money market funds
Included in cash and cash equivalents:
Amortized Cost	147,245	16,815
Estimated Fair Value	147,245	16,815
Restricted cash:
Amortized Cost	847	843
Estimated Fair Value	847	843
Commercial paper
Included in cash and cash equivalents:
Amortized Cost	1,498
Estimated Fair Value	1,498
Certificate of deposit
Restricted cash:
Amortized Cost	272	272
Estimated Fair Value	272	272
U.S. Treasury securities (due in less than one year)
Marketable securities:
Amortized Cost		26,752
Gross Unrealized Gains		95
Estimated Fair Value		26,847
U.S. Treasury securities (due in one to two years)
Marketable securities:
Amortized Cost	29,938	2,877
Gross Unrealized Gains	14	17
Gross Unrealized Losses	(2)
Estimated Fair Value	29,950	2,894
Government-sponsored enterprise securities (due in less than one year)
Marketable securities:
Amortized Cost	63,652	86,250
Gross Unrealized Gains	14	43
Gross Unrealized Losses	(79)	(92)
Estimated Fair Value	63,587	86,201
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	118,481	102,270
Gross Unrealized Gains	3	31
Gross Unrealized Losses	(157)	(33)
Estimated Fair Value	118,327	102,268
Corporate notes (due in less than one year)
Marketable securities:
Amortized Cost	41,458	48,409
Gross Unrealized Gains	5	14
Gross Unrealized Losses	(39)	(63)
Estimated Fair Value	41,424	48,360
Corporate notes (due in one to two years)
Marketable securities:
Amortized Cost	20,801	26,628
Gross Unrealized Gains	18	130
Gross Unrealized Losses	(37)	(24)
Estimated Fair Value	$ 20,782	$ 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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