Net Loss Per Common Share - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Earnings Per Share [Abstract]
Amounts allocated to participating securities	$ 0	$ 0	$ 0	$ 0
Participating securities outstanding, shares	0	0	0	0