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FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Included in cash and cash equivalents:
Amortized Cost	$ 36,824	$ 16,815
Gross Unrealized Gains	2
Estimated Fair Value	36,826	16,815
Restricted cash:
Amortized Cost	1,854	1,115
Estimated Fair Value	1,854	1,115
Marketable securities:
Amortized Cost	315,736	306,784
Gross Unrealized Gains	1,010	402
Gross Unrealized Losses	(4)	(212)
Estimated Fair Value	316,742	306,974
Money market funds
Included in cash and cash equivalents:
Amortized Cost	31,854	16,815
Estimated Fair Value	31,854	16,815
Restricted cash:
Amortized Cost	1,581	843
Estimated Fair Value	1,581	843
Commercial paper
Included in cash and cash equivalents:
Amortized Cost	4,970
Gross Unrealized Gains	2
Estimated Fair Value	4,972
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	35,481	26,752
Gross Unrealized Gains	56	95
Estimated Fair Value	35,537	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	19,680	86,250
Gross Unrealized Gains	27	43
Gross Unrealized Losses		(92)
Estimated Fair Value	19,707	86,201
Government-sponsored enterprise securities (due in one to two years)
Marketable securities:
Amortized Cost	5,000	13,598
Gross Unrealized Gains		72
Estimated Fair Value	5,000	13,670
Commercial paper (due in less than one year)
Marketable securities:
Amortized Cost	135,717	102,270
Gross Unrealized Gains	327	31
Gross Unrealized Losses	(1)	(33)
Estimated Fair Value	136,043	102,268
Corporate notes (due in less than one year)
Marketable securities:
Amortized Cost	87,816	48,409
Gross Unrealized Gains	327	14
Gross Unrealized Losses	(2)	(63)
Estimated Fair Value	88,141	48,360
Corporate notes (due in one to two years)
Marketable securities:
Amortized Cost	32,042	26,628
Gross Unrealized Gains	273	130
Gross Unrealized Losses	(1)	(24)
Estimated Fair Value	$ 32,314	$ 26,734

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