For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Strategic and License Agreements - Narrative (Details) - USD ($) $ in Thousands		1 Months Ended		12 Months Ended
	Oct. 24, 2014	Sep. 30, 2017	Oct. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Feb. 27, 2019
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Inventory write-down				$ 0	$ 2,232	$ 0
Payments to acquire global rights to preclinical development program			$ 1,500
Endo Ventures manufacturing and supply agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Cash received for reimbursements		$ 1,500
Net receivables		4,700
Raw materials		2,300
Notes payable		7,000
Contract termination fee		2,500
Contract termination costs				$ 500
Brabant Pharma Limited [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Aggregate amount of contingent liabilities	$ 95,000
Regulatory Milestones [Member] \| Brabant Pharma Limited [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Aggregate amount of contingent liabilities	50,000
Sales Milestones [Member] \| Brabant Pharma Limited [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Aggregate amount of contingent liabilities	$ 45,000
Sumavel DosePro [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Inventory write-down		2,200
Impairment of prepaid royalties		$ 2,000
Subsequent Event [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Contingent development milestone payment							$ 10,000