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Nature of Business - Additional Information (Detail) - USD ($)
$ in Thousands
Mar. 31, 2020
Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]    
Cash, cash equivalents, and short-term marketable securities $ 114,200  
Restricted cash 1,097 $ 1,097
Accumulated deficit $ (186,966) $ (171,138)