Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Accrued Expenses
Accrued compensation	$ 13,870	$ 9,145
Accrued professional fees	2,212	6,447
Accrued clinical trial and clinical supply costs	4,251	4,350
Accrued product costs	807	1,794
Accrued interest expense		61
Other accrued expenses	5,752	5,630
Total	$ 26,892	$ 27,427