Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Payables And Accruals [Abstract]
Development and clinical manufacturing costs	$ 6,443	$ 5,605
Payroll and payroll-related costs	3,921	4,609
Facility and other	954	670
Total accrued expenses and other current liabilities	$ 11,318	$ 10,884

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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