INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Apr. 02, 2015	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Intangible assets
Gross Carrying Amount			$ 1,098,588	$ 1,109,068
Accumulated amortization			(304,715)	(206,919)
Total			793,873	902,149
Amortization of intangible assets			102,745	106,845	$ 83,344
Future amortization expenses of intangible assets
2018			101,774
2019			101,774
2020			101,774
2021			101,774
2022			99,969
Thereafter			$ 286,808
NUCYNTA
Intangible assets
Remaining Useful Life (In years)	10 years
Product rights | NUCYNTA products
Intangible assets
Remaining Useful Life (In years)			8 years
Gross Carrying Amount			$ 1,019,978	1,019,978
Accumulated amortization			(266,590)	(172,288)
Total			$ 753,388	847,690
Product rights | NUCYNTA products | Change in amortization period
Intangible assets
Amortization of intangible assets		$ (1,300)
Product rights | CAMBIA
Intangible assets
Remaining Useful Life (In years)			6 years
Gross Carrying Amount			$ 51,360	51,360
Accumulated amortization			(20,755)	(15,619)
Total			$ 30,605	35,741
Product rights | Lazanda
Intangible assets
Gross Carrying Amount				10,480
Accumulated amortization				(3,979)
Total				6,501
Product rights | Zipsor
Intangible assets
Remaining Useful Life (In years)			4 years 3 months 18 days
Gross Carrying Amount			$ 27,250	27,250
Accumulated amortization			(17,370)	(15,033)
Total			9,880	$ 12,217
Product rights | Zipsor | Change in amortization period
Intangible assets
Amortization of intangible assets			$ (900)