Stockholders' Equity - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Outstanding at beginning of period	3,196,100	4,192,927	4,279,919
Number of Shares, Granted	684,629
Number of Shares, Exercised	(235,480)	(1,332,563)	(115,667)
Number of Shares, Forfeitures	(247,720)	(84,744)	(250,119)
Number of Shares, Outstanding at end of period	3,397,529	3,196,100	4,192,927
Weighted Average Exercise Price Per Share, Outstanding at beginning of period	$ 4.32	$ 3.82	$ 3.70
Weighted average Exercise Price Per Share, Exercised	3.52	3.48	3.25
Weighted Average Exercise Price Per Share, Forfeitures	12.65	5.26	2.89
Weighted Average Exercise Price Per Share, Outstanding at end of period	$ 5.42	$ 4.32	$ 3.82
Aggregate Intrinsic Value, Outstanding at beginning of period	$ 22,881	$ 9,146	$ 4,572
Aggregate Intrinsic Value, Outstanding at end of period	$ 3,124	$ 22,881	$ 9,146
Officers and Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Granted			55,659
Weighted Average Exercise Price Per Share, Granted			$ 5.39
Others [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Granted	684,629	420,480	223,135
Weighted Average Exercise Price Per Share, Granted	$ 8.14	$ 13.86	$ 4.47