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		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Basic Earnings (Loss) per Common Share:
Net loss	$ (4,240)	$ (5,198)	$ (17,401)	$ (15,916)
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	(4,240)	(5,198)	(17,401)	(15,916)
Undistributed earnings allocable to participating securities	0	0	0	0
Total undistributed loss	(4,240)	(5,198)	(17,401)	(15,916)
Loss to common shares—basic	$ (4,240)	$ (5,198)	$ (17,401)	$ (15,916)
Weighted average common shares outstanding—basic	10,797	9,506	10,410	8,878
Basic earnings (loss) per common share	$ (0.39)	$ (0.55)	$ (1.67)	$ (1.79)
Diluted Earnings (Loss) per Common Share:
Loss to common shares—basic	$ (4,240)	$ (5,198)	$ (17,401)	$ (15,916)
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	$ (4,240)	$ (5,198)	$ (17,401)	$ (15,916)
Weighted average common shares outstanding—basic	10,797	9,506	10,410	8,878
Dilutive effect of stock options	0	0	0	0
Weighted average common shares outstanding— dilutive	10,797	9,506	10,410	8,878
Diluted earnings (loss) per common share	$ (0.39)	$ (0.55)	$ (1.67)	$ (1.79)