Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Payables And Accruals [Abstract]
Development and manufacturing costs	$ 6,779	$ 7,046
Payroll and payroll-related costs	3,550	5,020
Facility and other	1,460	3,141
Total accrued expenses and other current liabilities	$ 11,789	$ 15,207

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
-Publisher FASB
-Name Accounting Standards Codification
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