Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Commercial costs and product revenue reserves	$ 12,584	$ 14,300
Research and development costs	10,112	8,406
Payroll and employee benefits	12,484	16,934
Interest	3,050	3,482
Restructuring costs	999	0
Professional fees	5,853	6,295
Other current liabilities	95	95
Total accrued expenses and other current liabilities	$ 45,177	$ 49,512