INTANGIBLE ASSETS AND GOODWILL - Summary of Gross Carrying Amounts and Net Book Values of Intangible Assets and Goodwill (Details) - USD ($) $ in Thousands		6 Months Ended
	May 20, 2020	Jun. 30, 2020	Dec. 31, 2019
Intangible assets
Gross Carrying Amount		$ 239,510	$ 1,098,588
Accumulated Amortization		(59,794)	(508,263)
Impairment			(189,790)
Total		179,716	400,535
Gross Carrying Amount, Goodwill		14,147	0
Goodwill		$ 14,147	0
Zyla Life Sciences
Intangible assets
Goodwill	$ 14,147
INDOCIN | Product Rights
Intangible assets
Remaining Useful Life (In years) (Less than 1 year)		5 years 10 months 24 days
Gross Carrying Amount		$ 107,500	0
Accumulated Amortization		(1,941)	0
Total		$ 105,559	0
SPRIX | Product Rights
Intangible assets
Remaining Useful Life (In years) (Less than 1 year)		5 years 10 months 24 days
Gross Carrying Amount		$ 52,500	0
Accumulated Amortization		(948)	0
Total		$ 51,552	0
CAMBIA | Product Rights
Intangible assets
Remaining Useful Life (In years) (Less than 1 year)		3 years 6 months
Gross Carrying Amount		$ 51,360	51,360
Accumulated Amortization		(33,595)	(31,027)
Total		$ 17,765	20,333
Zipsor | Product Rights
Intangible assets
Remaining Useful Life (In years) (Less than 1 year)		1 year 8 months 12 days
Gross Carrying Amount		$ 27,250	27,250
Accumulated Amortization		(23,213)	(22,044)
Total		4,037	5,206
Other | Product Rights
Intangible assets
Gross Carrying Amount		900	0
Accumulated Amortization		(97)	0
Total		$ 803	0
Other | Product Rights | Zyla Life Sciences
Intangible assets
Remaining Useful Life (In years) (Less than 1 year)	1 year	1 year
NUCYNTA | Product Rights
Intangible assets
Gross Carrying Amount		$ 0	1,019,978
Accumulated Amortization		0	(455,192)
Impairment			(189,790)
Total		$ 0	$ 374,996