SHARE-BASED COMPENSATION - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	9 Months Ended		93 Months Ended
	Jun. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance (in shares)		4,576,697		4,576,697
Unrecognized option employee stock-based compensation costs		$ 106.7		$ 106.7
Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, acceleration of vesting		7.5
Plan modification costs		1.6
Chief Financial Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, acceleration of vesting		$ 1.2
Options to Purchase Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period		10 years
Vesting period (up to)		48 months
Weighted average fair value per option (in usd per share)		$ 23.19	$ 11.92
Remaining weighted-average period for RSUs		3 years 1 month 9 days
Options to Purchase Common Stock | Initial Vesting Period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent		25.00%
Options to Purchase Common Stock | Subsequent Vesting Period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent		75.00%
Vesting period (up to)		36 months
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price of common stock, percentage of fair market value		85.00%
Stock purchase offering period		6 months
Shares available for issuance (in shares)		691,384		691,384
Issuance of common stock for cash under employee stock purchase plan (in shares)				58,290
Restricted Stock Units Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining weighted-average period for RSUs		3 years 4 months 6 days
Unrecognized employee stock-based compensation costs related to unvested RSUs		$ 10.1		$ 10.1
2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares authorized for plan (in shares)	2,000,000
Shares available for issuance (in shares)		4,576,697		4,576,697