v3.19.2
Property and Equipment - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Property Plant And Equipment [Abstract]        
Depreciation and amortization expense $ 116 $ 50 $ 238 $ 89