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LICENSE, COLLABORATION AND OTHER REVENUE - MTPC Collaboration Agreement - Narrative (Details) $ in Thousands		3 Months Ended		6 Months Ended
	Dec. 11, 2015 USD ($) performance_obligation	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues		$ 49,128	$ 62,472	$ 102,672	$ 119,808
Accounts receivable, net		53,506		53,506		$ 47,031
Payables		9,422		9,422		$ 21,185
Revenue recognized		0	0	0	0
Royalty payments
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues		100	0	100	0
Tanabe Pharma Corporation
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues	$ 9,400
Tanabe Pharma Corporation \| Royalty payments
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues		400	500	800	900
Tanabe Pharma Corporation \| Regulatory Milestone Payments
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone revenue	$ 25,000			25,000
Tanabe Pharma Corporation \| Development And Commercialize Collaboration Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of performance obligations \| performance_obligation	2
Tanabe Pharma Corporation \| Development And Commercialize Research And License Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront cash payment received	$ 20,000
Cost of research services	20,500
Milestone revenue	$ 10,000
Deferred revenue		0		0
Accounts receivable, net		0		0
Payables		0		0
Contract asset		400		400
Tanabe Pharma Corporation \| Mitsubishi Tanabe Pharma Corporation Supply Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deferred revenue		0		0
Accounts receivable, net		0		0
Payables		0		0
Revenue recognized		$ 0	$ 0	$ 0	$ 0