Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Payables And Accruals [Abstract]
Development and manufacturing costs	$ 3,763	$ 3,350
Payroll and payroll-related costs	2,707	3,698
Professional fees	505	448
Facility and other	2,743	3,316
Total Accrued Expenses and Other Current Liabilities	$ 9,718	$ 10,812