SEGMENT REPORTING - Revenue (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025 USD ($) brand productFamily	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) productFamily segment brand reportingUnit	Jun. 30, 2024 USD ($)
Segment reporting
Number of operating segments | segment			2
Number of reporting units | segment			3
Established brand products | brand	20		20
Product families | productFamily	100		100
Net Revenues	$ 211,371	$ 138,040	$ 408,493	$ 275,470
Cost of sales (excluding depreciation and amortization)	74,615	57,698	147,652	106,855
Research and development expense	16,535	7,296	27,099	17,807
Selling, general, and administrative	81,771	52,821	158,299	100,842
Depreciation and amortization	23,281	14,697	46,172	29,383
Contingent consideration fair value adjustment	1,277	359	(10,815)	449
Gain on sale of building	0	0	0	(5,347)
Operating income	13,892	5,169	40,086	25,481
Unrealized gain (loss) on investment in equity securities	332	(2,712)	(589)	6,943
Interest expense, net	(5,438)	(4,656)	(10,922)	(9,256)
Other income (expense), net	1,739	(88)	1,937	(120)
Income (Loss) Before Income Tax Expense	10,525	(2,287)	$ 30,512	23,048
Rare Disease and Brands
Segment reporting
Number of reporting units | reportingUnit			2
Operating Segments | Generics and Other
Segment reporting
Net Revenues	94,213	78,821	$ 197,253	153,635
Cost of sales (excluding depreciation and amortization)	43,231	42,014	89,732	78,814
Research and development expense	11,414	5,427	18,002	13,446
Selling, general, and administrative	1,389	1,344	2,797	2,354
Depreciation and amortization	0	0	0	0
Contingent consideration fair value adjustment	0	0	0	0
Gain on sale of building		0		0
Operating income	38,179	30,036	86,722	59,021
Unrealized gain (loss) on investment in equity securities	0	0	0	0
Interest expense, net	0	0	0	0
Other income (expense), net	0	0	0	0
Income (Loss) Before Income Tax Expense	38,179	30,036	86,722	59,021
Operating Segments | Rare Disease and Brands
Segment reporting
Net Revenues	117,158	59,219	211,240	121,835
Cost of sales (excluding depreciation and amortization)	31,384	15,684	57,920	28,041
Research and development expense	5,121	1,869	9,097	4,361
Selling, general, and administrative	51,191	26,349	93,627	51,015
Depreciation and amortization	0	0	0	0
Contingent consideration fair value adjustment	0	0	0	0
Gain on sale of building		0		0
Operating income	29,462	15,317	50,596	38,418
Unrealized gain (loss) on investment in equity securities	0	0	0	0
Interest expense, net	0	0	0	0
Other income (expense), net	0	0	0	0
Income (Loss) Before Income Tax Expense	29,462	15,317	50,596	38,418
Corporate and Unallocated
Segment reporting
Net Revenues	0	0	0	0
Cost of sales (excluding depreciation and amortization)	0	0	0	0
Research and development expense	0	0	0	0
Selling, general, and administrative	29,191	25,128	61,875	47,473
Depreciation and amortization	23,281	14,697	46,172	29,383
Contingent consideration fair value adjustment	1,277	359	(10,815)	449
Gain on sale of building		0		(5,347)
Operating income	(53,749)	(40,184)	(97,232)	(71,958)
Unrealized gain (loss) on investment in equity securities	332	(2,712)	(589)	6,943
Interest expense, net	(5,438)	(4,656)	(10,922)	(9,256)
Other income (expense), net	1,739	(88)	1,937	(120)
Income (Loss) Before Income Tax Expense	$ (57,116)	$ (47,640)	$ (106,806)	$ (74,391)