FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Included in cash and cash equivalents:
Amortized Cost	$ 16,519	$ 39,771
Estimated Fair Value	16,519	39,771
Restricted cash:
Amortized Cost	536	364
Estimated Fair Value		364
Marketable securities:
Amortized Cost	351,602	116,142
Gross Unrealized Gains	9	6
Gross Unrealized Losses	(972)	(247)
Estimated Fair Value	350,639	115,901
Money market funds
Included in cash and cash equivalents:
Amortized Cost	12,549	39,771
Estimated Fair Value	12,549	39,771
Restricted cash:
Amortized Cost	264	93
Estimated Fair Value	264	93
Commercial paper
Included in cash and cash equivalents:
Amortized Cost	3,970
Estimated Fair Value	3,970
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		12,983
Gross Unrealized Losses		(62)
Estimated Fair Value		12,921
U.S. Treasury securities - due in 1 to 2 years
Marketable securities:
Amortized Cost	26,467
Gross Unrealized Gains	1
Gross Unrealized Losses	(22)
Estimated Fair Value	26,446
Municipal securities (due in less than one year)
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	94,524	9,860
Gross Unrealized Gains	4
Gross Unrealized Losses	(293)	(14)
Estimated Fair Value	94,235	9,846
Government-sponsored enterprise securities (due in one to two years)
Marketable securities:
Amortized Cost	10,651
Gross Unrealized Losses	(35)
Estimated Fair Value	10,616
Commercial paper (due in less than one year)
Marketable securities:
Amortized Cost	149,583	64,285
Gross Unrealized Gains	1	6
Gross Unrealized Losses	(280)	(92)
Estimated Fair Value	149,304	64,199
Corporate notes (due in less than one year)
Marketable securities:
Amortized Cost	39,438	26,014
Gross Unrealized Gains	2
Gross Unrealized Losses	(160)	(55)
Estimated Fair Value	39,280	$ 25,959
Corporate notes (due in one to two years)
Marketable securities:
Amortized Cost	30,939
Gross Unrealized Gains	1
Gross Unrealized Losses	(182)
Estimated Fair Value	$ 30,758

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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