Annual report pursuant to Section 13 and 15(d)

Property and Equipment - Additional Information (Detail)

v3.20.1
Property and Equipment - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Property Plant And Equipment [Line Items]    
Depreciation expense $ 2.0 $ 1.0
Leasehold Improvements    
Property Plant And Equipment [Line Items]    
Asset retirement obligation, asset $ 1.0 $ 0.1