SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Revenue and Gross Accounts Receivable By Major Customer (Details) - Customer Concentration Risk	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
% of Total Gross Revenues | Fresenius Medical Care Rx
Concentration Risk [Line Items]
Concentration risk percentage	40.00%	34.00%
% of Total Gross Revenues | Cencora, Inc., formerly known as AmerisourceBergen Drug Corporation
Concentration Risk [Line Items]
Concentration risk percentage	21.00%	15.00%
% of Total Gross Revenues | McKesson Corporation
Concentration Risk [Line Items]
Concentration risk percentage	11.00%	0.00%
% of Total Gross Revenues | Cardinal Health, Inc.
Concentration Risk [Line Items]
Concentration risk percentage	10.00%	0.00%
% of Total Gross Revenues | Otsuka Pharmaceutical Co. Ltd.
Concentration Risk [Line Items]
Concentration risk percentage	0.00%	20.00%
% of Gross Accounts Receivable | Fresenius Medical Care Rx
Concentration Risk [Line Items]
Concentration risk percentage	31.00%	44.00%
% of Gross Accounts Receivable | Cencora, Inc., formerly known as AmerisourceBergen Drug Corporation
Concentration Risk [Line Items]
Concentration risk percentage	25.00%	16.00%
% of Gross Accounts Receivable | McKesson Corporation
Concentration Risk [Line Items]
Concentration risk percentage	12.00%	10.00%
% of Gross Accounts Receivable | Cardinal Health, Inc.
Concentration Risk [Line Items]
Concentration risk percentage	16.00%	13.00%