Other Assets and Liabilities - Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Accrued Expenses
Accrued compensation	$ 2,147	$ 3,157
Accrued social charges	1,071	1,204
Accrued employee severance (see Note 13)	581	1,000
Customer allowances	5,583	10,613
Accrued Exclusive License and Assignment Agreement (ELAA) payment	0	20,000
Accrued contract research organization charges	1,880	156
Accrued contract manufacturing organization costs	2,578	2,327
Accrued contract sales organization and marketing costs	4,156	7,641
Other	2,702	4,828
Total	$ 20,698	$ 50,926