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Summary of Significant Accounting Policies - Narrative (Details) (USD $)	3 Months Ended				12 Months Ended			0 Months Ended	1 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2014 segment	Dec. 31, 2013	Dec. 31, 2012	May 16, 2014	May 31, 2014	Dec. 31, 2014	Dec. 31, 2009
Accounting Policies [Abstract]
Letter of credit											$ 200,000
Restricted cash	0				0	200,000				0
Allowance for doubtful accounts	102,000				102,000	18,000				102,000
Payment discounts					59,000us-gaap_SalesDiscountsGoods	118,000us-gaap_SalesDiscountsGoods
Concentration Risk [Line Items]
Period to accept returned unused product after product expiration					1 year
Impairment of long-lived assets	0	0	838,000	0	838,000	0	0
Advertising expense					6,062,000us-gaap_AdvertisingExpense	1,330,000us-gaap_AdvertisingExpense	1,333,000us-gaap_AdvertisingExpense
Foreign currency gains (losses)					(145,000)	(95,000)	(68,000)
Number of operating segments					1us-gaap_NumberOfOperatingSegments
Sales Revenue, Product Line [Member]
Concentration Risk [Line Items]
Number of customers					3
Accounts Receivable [Member]
Concentration Risk [Line Items]
Number of customers					3
Pharmaceutical Distributor, Customer One [Member] \| Sales Revenue, Product Line [Member]
Concentration Risk [Line Items]
Concentration risk					33.00%
Pharmaceutical Distributor, Customer Two [Member] \| Sales Revenue, Product Line [Member]
Concentration Risk [Line Items]
Concentration risk					32.00%
Pharmaceutical Distributor, Customer Three [Member] \| Sales Revenue, Product Line [Member]
Concentration Risk [Line Items]
Concentration risk					23.00%
Pharmaceutical Distributor, Customer One, Two and Three [Member] \| Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration risk					79.00%
Minimum [Member]
Concentration Risk [Line Items]
Rebate repayment period					2 months
Maximum [Member]
Concentration Risk [Line Items]
Rebate repayment period					3 months
Sumavel DosePro [Member]
Concentration Risk [Line Items]
Cost of goods sold mark-up, in percent								2.50%	2.50%
Restricted cash and cash equivalents	8,500,000				8,500,000					8,500,000
Potential indemnification period								12 months	12 months
Contract Manufacturing [Member] \| Sales Revenue, Product Line [Member]
Concentration Risk [Line Items]
Number of customers					1
Sumavel DosePro [Member]
Concentration Risk [Line Items]
Period to accept returned unused product after product expiration					1 year
Number of subassemblies					2
Endo Ventures Supply Agreement [Member] \| Minimum [Member]
Concentration Risk [Line Items]
Term of agreement										8 years
Cost of Sales [Member] \| Zohydro ER [Member]
Concentration Risk [Line Items]
Inventory adjustments					5,769,000
Cost of Goods, Total [Member] \| Zohydro ER [Member]
Concentration Risk [Line Items]
Non-cancellable purchase commitment adjustment					$ 2,594,000