FAIR VALUE MEASUREMENTS - Debt Securities, Available-for-sale (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 308,633	$ 424,840
Gross Unrealized Gains	7	124
Gross Unrealized Losses	(71)	(514)
Fair Value	308,569	424,450
Money market funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	102,982	137,903
Gross Unrealized Gains	3	0
Gross Unrealized Losses	0	0
Fair Value	102,985	137,903
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	44,386	85,578
Gross Unrealized Gains	2	123
Gross Unrealized Losses	(20)	(96)
Fair Value	44,368	85,605
U.S. corporate paper and bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	161,265	199,350
Gross Unrealized Gains	2	1
Gross Unrealized Losses	(51)	(385)
Fair Value	$ 161,216	198,966
International corporate bond holdings
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		2,009
Gross Unrealized Gains		0
Gross Unrealized Losses		(33)
Fair Value		$ 1,976