Earnings Per Common Share - Summary of Reconciliation of Earnings (Loss) Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Basic Earnings (Loss) per Common Share:
Net loss	$ (6,943)	$ (5,283)	$ (13,161)	$ (10,718)
Distributed earnings to common shares	0	0	0	0
Distributed earnings to participating securities	0	0	0	0
Total distributed earnings	0	0	0	0
Undistributed loss allocable to common shares	(6,943)	(5,283)	(13,161)	(10,718)
Undistributed earnings allocable to participating securities	0	0	0	0
Total undistributed loss	(6,943)	(5,283)	(13,161)	(10,718)
Loss to common shares—basic	$ (6,943)	$ (5,283)	$ (13,161)	$ (10,718)
Weighted average common shares outstanding—basic	10,266	8,587	10,214	8,560
Basic earnings (loss) per common share	$ (0.68)	$ (0.62)	$ (1.29)	$ (1.25)
Diluted Earnings (Loss) per Common Share:
Loss to common shares—basic	$ (6,943)	$ (5,283)	$ (13,161)	$ (10,718)
Undistributed earnings allocated to participating securities	0	0	0	0
Undistributed earnings reallocated to participating securities	0	0	0	0
Loss to common shares—diluted	$ (6,943)	$ (5,283)	$ (13,161)	$ (10,718)
Weighted average common shares outstanding—basic	10,266	8,587	10,214	8,560
Dilutive effect of stock options	0	0	0	0
Weighted average common shares outstanding— dilutive	10,266	8,587	10,214	8,560
Diluted earnings (loss) per common share	$ (0.68)	$ (0.62)	$ (1.29)	$ (1.25)