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STOCK INCENTIVE PLAN AND STOCK-BASED COMPENSATION - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Apr. 30, 2021	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Stock Incentive Plan and Stock-based Compensation
Weighted average period				2 years 4 months 24 days
Employee Stock Option
Stock Incentive Plan and Stock-based Compensation
Unrecognized stock-based compensation expense		$ 59,799		$ 59,799
Restricted Stock Units
Stock Incentive Plan and Stock-based Compensation
Weighted average per share fair value of awards issued (in USD per share)				$ 30.62
Unrecognized stock-based compensation expense		$ 17,533		$ 17,533
2020 Plan
Stock Incentive Plan and Stock-based Compensation
Stock options contractual term				10 years
Total number of shares available for issuance		6,836,036		6,836,036
Percentage of increment of common stock outstanding				4.00%
2017 and 2020 Plans \| Restricted Stock Units
Stock Incentive Plan and Stock-based Compensation
Weighted average per share fair value of awards issued (in USD per share)				$ 21.25		$ 20.64
Employee Stock Purchase Plan
Stock Incentive Plan and Stock-based Compensation
Total number of shares available for issuance	629,805
Percentage of increment of common stock outstanding	1.00%
ESPP permits eligible employees to purchase shares of common stock at discount	15.00%
Shares issued under the ESPP		1,206	0	11,913	14,043
Amount of discount on ESSP		$ 72	$ 100	$ 230	$ 308