Earnings Per Share - Details of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator:
Net income (loss)	$ 3,436	$ (2,177)	$ 3,484	$ (4,558)
Dividends paid to preferred stockholders	(34)	(185)	(67)	(326)
Net income (loss) available to common stockholders	$ 3,402	$ (2,362)	$ 3,417	$ (4,884)
Denominator:
Weighted average shares outstanding – basic	32,068	21,888	31,685	18,612
Potential common shares – options / warrants (treasury stock method)	3,240		1,680
Weighted average shares outstanding – diluted	35,308	21,888	33,365	18,612
Shares excluded due to an exercise price greater than weighted average stock price for the period	125	7,100	125	3,930
Net earnings (loss) per common share:
Basic	$ 0.11	$ (0.11)	$ 0.11	$ (0.26)
Diluted	$ 0.10	$ (0.11)	$ 0.10	$ (0.26)