INTANGIBLE ASSETS (Tables)

9 Months Ended

Sep. 30, 2018

Finite-Lived Intangible Assets, Net [Abstract]

Summary of the gross carrying amounts and net book values of our intangible assets

The gross carrying amounts and net book values of our intangible assets were as follows (in thousands):

	September 30, 2018								December 31, 2017
	Remaining	Gross							Gross
	Useful Life	Carrying		Accumulated			Net Book		Carrying		Accumulated			Net Book
Product rights	(In years)	Amount		Amortization			Value		Amount		Amortization			Value
NUCYNTA	7.2	$	1,019,978	$	(337,316	)	$	682,662	$	1,019,978	$	(266,590	)	$	753,388
CAMBIA	5.2	51,360		(24,607		)	26,753		51,360		(20,755		)	30,605
Zipsor	3.5	27,250		(19,123		)	8,127		27,250		(17,370		)	9,880
Total		$	1,098,588	$	(381,046	)	$	717,542	$	1,098,588	$	(304,715	)	$	793,873

Summary of the future amortization expenses of intangible assets

Based on finite-lived intangible assets recorded as of September 30, 2018, and assuming the underlying assets will not be impaired and that the Company will not change the expected lives of the assets, future amortization expenses were estimated as follows (in thousands):

	Estimated
	Amortization
Year Ending December 31,	Expense
2018 (remainder)	$	25,443
2019	101,774
2020	101,774
2021	101,774
2022	99,969
Thereafter	286,808
Total	$	717,542