Accounts Payable and Accrued Expenses - Schedule of Accounts Payable and Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Payables And Accruals [Abstract]
Accounts payable	$ 9,309	$ 9,100
Accrued research projects	5,699	6,637
Accrued professional fees	736	635
Accrued compensation and benefits	1,627	3,293
Total	$ 17,371	$ 19,665