SEGMENT REPORTING - Revenue (Details) $ in Thousands		12 Months Ended
	Dec. 31, 2021 segment	Dec. 31, 2023 USD ($) segment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Segment reporting
Number of segments | segment	1	2
Total net revenues		$ 486,816	$ 316,385	$ 216,136
Depreciation and amortization		59,791	56,972	47,252
Corporate and other unallocated expenses		161,697	124,044	84,294
Operating Income (Loss)		46,971	(35,283)	(39,793)
Interest expense, net		(26,940)	(28,052)	(11,922)
Other (expense) income, net		(159)	670	(4,343)
Income (Loss) Before Expense (Benefit) for Income Taxes		19,872	(62,665)	(56,058)
Operating Segments | Generics, Established Brands and Other
Segment reporting
Total net revenues		374,699	274,699	216,136
EBITDA		152,990	78,958	63,418
Operating Segments | Rare Disease
Segment reporting
Total net revenues		112,117	41,686	0
EBITDA		12,498	(18,348)	(18,571)
Segment Reconciling Items
Segment reporting
Depreciation and amortization		(59,791)	(56,973)	(47,252)
Corporate, Non-Segment
Segment reporting
Corporate and other unallocated expenses		$ (58,726)	$ (38,920)	$ (37,388)