INTANGIBLE ASSETS (Tables)

12 Months Ended

Dec. 31, 2016

INTANGIBLE ASSETS.

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):

	December 31, 2016							December 31, 2015
	Remaining	Gross						Gross
	Useful Life	Carrying		Accumulated		Net Book		Carrying		Accumulated		Net Book
Amounts in thousands	(In years)	Amount		Amortization		Value		Amount		Amortization		Value
NUCYNTA product rights	9.0	$	1,019,978	$	(172,288)	$	847,690	$	1,019,978	$	(74,081)	$	945,897
CAMBIA product rights	7.0		51,360		(15,619)		35,741		51,360		(10,483)		40,877
Lazanda product rights	5.6		10,480		(3,979)		6,501		10,480		(2,814)		7,666
Zipsor product rights	5.3		27,250		(15,033)		12,217		27,250		(12,696)		14,554
		$	1,109,068	$	(206,919)	$	902,149	$	1,109,068	$	(100,074)	$	1,008,994

Summary of the future amortization expenses of intangible assets

Based on finite-lived intangible assets recorded as of December 31, 2016, and assuming the underlying assets will not be impaired and that we 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
2017	$	102,939
2018		102,939
2019		102,939
2020		102,939
2021		102,939
Thereafter		387,454
Total	$	902,149