REVENUE RECOGNITION - Schedule of Net Product Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue [Line Items]
Total net product sales	$ 169,584	$ 114,449	$ 296,782	$ 196,180
Total net product sales
Disaggregation of Revenue [Line Items]
Total net product sales	161,352	94,842	285,844	170,702
FILSPARI
Disaggregation of Revenue [Line Items]
Total net product sales	141,078	71,887	246,230	127,768
Tiopronin products
Disaggregation of Revenue [Line Items]
Total net product sales	$ 20,274	$ 22,955	$ 39,614	$ 42,934

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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