ACQUISITIONS (Details) $ / shares in Units, $ in Thousands						3 Months Ended	9 Months Ended	12 Months Ended
	Nov. 17, 2015 USD ($) patent	Apr. 02, 2015 USD ($)	Dec. 17, 2013 USD ($)	Jul. 29, 2013 USD ($)	Jun. 21, 2012 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) shares
Purchase price consideration
Cash Paid								$ 1,050,011		$ 52,725
Research and development expense								17,541	$ 7,116	8,073
Fair values of tangible and identifiable intangible assets acquired and liabilities assumed
Bargain purchase										$ (484)
Other information
Business acquisition step up in value of inventories						$ 0	$ 0	$ 0	$ 200
Pro forma financial information (unaudited)
Shares used in computing basic net income (loss) per share (in shares) | shares								60,116,530	58,292,633	56,736,009
Shares used in computing diluted net income (loss) per share (in shares) | shares								60,116,530	66,307,364	57,543,979
Endo
ACQUISITIONS
Number of patents infringed | patent	3
Cebranopadol
Purchase price consideration
Cash Paid	$ 25,000
Research and development expense	54,900
Cebranopadol | Endo
Purchase price consideration
Amount of one-time accounting adjustment	29,900
Cebranopadol | Endo | Non-cash gain on settlement agreement
Purchase price consideration
Amount of one-time accounting adjustment	(29,900)
Cebranopadol | Endo | Acquired in-process research and development expense
Purchase price consideration
Amount of one-time accounting adjustment	$ 29,900
NUCYNTA
Purchase price consideration
Cash Paid		$ 1,050,000
Rebates Payable By Seller		9,977
Total Purchase Consideration		1,040,023
Amount of decrease in the rebate payment						500
Amount of rebate payable estimated on the acquisition date		10,500
Increase in the purchase consideration and fair value of NUCYNTA U.S product rights						$ 500
Fair values of tangible and identifiable intangible assets acquired and liabilities assumed
Intangible asset - acquired entity product rights		1,019,978
Inventories		11,590
Manufacturing Equipment		8,455
Total		1,040,023
Other information
Business acquisition step up in value of inventories		$ 5,900
Pro forma financial information (unaudited)
Pro forma revenues								$ 387,693	$ 561,481
Proforma net (loss) income								$ (88,964)	$ 62,581
Pro forma net income per share - basic (in dollars per share) | $ / shares								$ (1.48)	$ 1.07
Pro forma net income per share - diluted (in dollars per share) | $ / shares								$ (1.48)	$ 1.01
Shares used in computing basic net income (loss) per share (in shares) | shares								60,116,530	58,292,633
Shares used in computing diluted net income (loss) per share (in shares) | shares								60,116,530	66,307,364
Revenues							$ 189,800
NUCYNTA | Selling general and administrative expense
Fair values of tangible and identifiable intangible assets acquired and liabilities assumed
Business Combination, Acquisition Related Costs								$ 12,300
CAMBIA
ACQUISITIONS
Contingent consideration potential, maximum			$ 5,000
Amounts held in escrow to be applied towards indemnification obligations			$ 7,500
Initial payments held in escrow, holding period			24 months
Purchase price consideration
Cash Paid			$ 48,725
Fair Value of contingent consideration			1,010
Total Purchase Consideration			49,735
Fair values of tangible and identifiable intangible assets acquired and liabilities assumed
Intangible asset - acquired entity product rights			51,360
Inventories			3,837
Other assets			409
Sales reserve liabilities			(1,847)
Unfavorable contract assumed			(3,540)
Bargain purchase			(484)
Total			49,735
Other information
Business acquisition step up in value of inventories			3,700
Business acquisition cost of sales related to the step-up value								3,500	$ 200
CAMBIA | Selling general and administrative expense
Other information
Acquisition related costs										$ 100
CAMBIA | Maximum
ACQUISITIONS
Contingent consideration, net sales threshold triggering milestone payments			100,000
CAMBIA | Third party
ACQUISITIONS
Contingent consideration payable			$ 10,000
CAMBIA | Third party | Maximum
Purchase price consideration
Royalties as a percentage of net sales			11.00%
Lazanda
ACQUISITIONS
Amounts held in escrow to be applied towards indemnification obligations				$ 1,000
Initial payments held in escrow, holding period				18 months
Purchase price consideration
Cash Paid				$ 4,000
Fair Value of contingent consideration				8,004
Total Purchase Consideration				12,004
Fair values of tangible and identifiable intangible assets acquired and liabilities assumed
Intangible asset - acquired entity product rights				10,450
Inventories				1,334
Other assets				116
Property, plant and equipment				356
Current liabilities				(283)
Goodwill				31
Total				12,004
Other information
Business acquisition step up in value of inventories				600
Business acquisition cost of sales related to the step-up value								$ 200	$ 300	100
Lazanda | Selling general and administrative expense
Other information
Acquisition related costs										$ 100
Lazanda | Net Sales, first year, level one
ACQUISITIONS
Contingent consideration payable				1,000
Lazanda | Net Sales, first year, level two
ACQUISITIONS
Contingent consideration payable				2,500
Lazanda | Net Sales, first year, level three
ACQUISITIONS
Contingent consideration payable				5,000
Lazanda | Net Sales, first year, level four
ACQUISITIONS
Contingent consideration payable				7,500
Lazanda | Minimum | Net Sales, first year, level one
ACQUISITIONS
Contingent consideration, net sales threshold				20,000
Lazanda | Minimum | Net Sales, first year, level two
ACQUISITIONS
Contingent consideration, net sales threshold				45,000
Lazanda | Minimum | Net Sales, first year, level three
ACQUISITIONS
Contingent consideration, net sales threshold				75,000
Lazanda | Minimum | Net Sales, first year, level four
ACQUISITIONS
Contingent consideration, net sales threshold				$ 100,000
Lazanda | Maximum
ACQUISITIONS
Royalties as a percentage of net sales in remainder of fiscal year				5.00%
Royalties as a percentage of net sales in 2014				5.00%
Lazanda | Third party | Minimum
ACQUISITIONS
Royalties as a percentage of net sales after 2014				13.00%
Lazanda | Third party | Maximum
ACQUISITIONS
Royalties as a percentage of net sales after 2014				15.00%
Zipsor
Purchase price consideration
Cash Paid					$ 26,436
Fair Value of contingent consideration					1,303
Total Purchase Consideration					27,739
Fair values of tangible and identifiable intangible assets acquired and liabilities assumed
Intangible asset - acquired entity product rights					27,100
Inventories					2,428
Other assets					100
Property, plant and equipment					43
Current liabilities					(1,840)
Bargain purchase					(92)
Total					27,739
Zipsor | Net Sales, first year, level one
ACQUISITIONS
Contingent consideration potential, maximum					2,000
Contingent consideration, net sales threshold					30,000
Zipsor | Net Sales, first year, level two
ACQUISITIONS
Contingent consideration payable					3,000
Contingent consideration, net sales threshold					$ 60,000