Summary of Significant Accounting Policies - Additional Information (Details)		3 Months Ended		6 Months Ended
	Jul. 01, 2015	Jun. 30, 2015 USD ($) segment	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Line of Credit Facility [Line Items]
Number of business segments | segment		1
Unrealized loss on available-for-sale securities		$ (1,552,000)	$ 0	$ (1,552,000)	$ 0
Zohydro ER
Line of Credit Facility [Line Items]
Restricted cash		10,000,000		$ 10,000,000
Sumavel DosePro
Line of Credit Facility [Line Items]
Cost of goods sold mark-up, in percent				2.50%
Restricted cash						$ 8,500,000
Endo Ventures Supply Agreement | Minimum
Line of Credit Facility [Line Items]
Term of supply agreement				8 years
Zohydro ER and Sumavel DosePro
Line of Credit Facility [Line Items]
Period to accept returned unused product prior to expiration				6 months
Period to accept returned unused product after product expiration				12 months
Short-term investments
Line of Credit Facility [Line Items]
Available-for-sale Securities		10,000,000		$ 10,000,000
Fair Value Inputs, Discount for Lack of Marketability		$ 900,000		$ 900,000
Subsequent event
Line of Credit Facility [Line Items]
Common stock conversion ratio	0.125