COLLABORATION AND LICENSING AGREEMENTS - Recognized Revenue (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue	$ 97,662		$ 73,222	$ 171,776	$ 119,245
Licensing revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue	20		19	5,040	36
Licensing revenue | Fosun Agreement | Fosun Pharma
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue	0	$ 5,000	0	5,000	0
Licensing revenue | Knight Agreement | Knight
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue	20		19	40	36
Product supply revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue	6,185		13	6,439	2,139
Product supply revenue | Knight Agreement | Knight
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue	0		0	254	0
Product supply revenue | 2017 KKC Agreement | Kyowa Kirin
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue	6,185		13	6,185	2,139
Non-cash royalty revenue related to the sale of future royalties
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue	1,380		599	2,406	967
Non-cash royalty revenue related to the sale of future royalties | 2017 KKC Agreement | Kyowa Kirin
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue	$ 1,380		$ 599	$ 2,406	$ 967