Net Income (Loss) Per Share - Computation of Basic and Diluted Net Income Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 28, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Net (loss) income		$ 781	$ 1,071	$ (7,246)	$ 3,704
Weighted average number of shares outstanding:
Weighted average common shares outstanding (shares)		41,723,667	41,103,502	41,512,189	40,910,381
Weighted average shares outstanding for basic earnings per share (shares)		41,723,667	41,103,502	41,512,189	40,910,381
Effect of share-based equity award plan (shares)	188,875	1,757,725	2,047,737	0	2,263,820
Weighted average shares outstanding for diluted earnings per share (shares)		43,481,392	43,151,239	41,512,189	43,174,201
Net income (loss) per share:
Basic (USD per share)		$ 0.02	$ 0.03	$ (0.17)	$ 0.09
Diluted (USD per share)		$ 0.02	$ 0.02	$ (0.17)	$ 0.09