DEFERRED REVENUE, REFUND LIABILITY AND LIABILITY RELATED TO SALE OF FUTURE ROYALTIES - Summary of Deferred Revenue Balances (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Current portion of deferred revenue	$ 43,296	$ 0
Deferred revenue, net of current portion	0	$ 43,296
Contract with Customer, Liability, Total	43,296
Vifor (International) Ltd.
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Current portion of deferred revenue	43,296
Deferred revenue, net of current portion	0
Contract with Customer, Liability, Total	$ 43,296