REVENUE (Tables)

12 Months Ended

Dec. 31, 2019

Revenue from Contract with Customer [Abstract]

Schedule of disaggregated revenue from contracts with customers

The following table summarizes revenue from contracts with customers for the years ended December 31, 2019, 2018 and 2017 (in thousands) into categories that depict how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors:

	Year ended December 31,
	2019			2018		2017
Product sales, net:
Gralise	$	63,124		$	58,077	$	77,034
CAMBIA	32,453			35,803		31,597
Zipsor	12,498			16,387		16,700
Total neurology product sales, net	108,075			110,267		125,331
NUCYNTA products	927			18,944		239,539
Lazanda	(196		)	755		15,010
Total product sales, net	108,806			129,966		379,880
Commercialization agreement:
Commercialization rights and facilitation services, net	118,614			100,038		—
Revenue from transfer of inventory	—			55,705		—
Royalties and milestone revenue	2,084			26,061		844
Total revenues	$	229,504		$	311,770	$	380,724

Summary of contract assets and liabilities

The following table presents changes in the Company’s contract assets as of December 31, 2019 (in thousands):

	Balance as of							Balance as of
	December 31, 2018		Additions		Deductions			December 31, 2019
Contract assets:
Contract asset - CAMBIA Canada	$	—	$	300	$	(300	)	$	—
Contract asset - Collegium, net	2,416		783		(1,303		)	1,896
	$	2,416	$	1,083	$	(1,603	)	$	1,896