Quarterly report pursuant to Section 13 or 15(d)

Property and Equipment - Additional Information (Detail)

v3.19.3
Property and Equipment - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Sep. 30, 2018
Dec. 31, 2018
Property Plant And Equipment [Line Items]          
Depreciation expense $ 0.5 $ 0.4 $ 1.3 $ 0.6  
Asset retirement obligation 0.4   0.4    
R&D Facility          
Property Plant And Equipment [Line Items]          
Asset retirement obligation, asset 0.4 0.0 0.4 0.0  
Asset retirement obligation 0.4 0.0 0.4 0.0  
cGMP Facility          
Property Plant And Equipment [Line Items]          
Asset retirement obligation, asset 0.4 0.0 0.4 0.0  
Asset retirement obligation 0.4 $ 0.0 0.4 $ 0.0  
Leasehold Improvements          
Property Plant And Equipment [Line Items]          
Asset retirement obligation, asset $ 0.9   $ 0.9   $ 0.1