Net Income (Loss) Per Share - Computation of Basic and Diluted Net Income (Loss) Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Net income (loss)	$ 287	$ (3,018)	$ 315	$ 486	$ 21,968	$ 2,120	$ 3,469	$ 511	$ (1,930)	$ 28,068	$ 9,180
Weighted average common basic shares									41,030	40,985	40,930
Effect of dilutive securities										298	162
Weighted average common dilutive shares									41,030	41,283	41,092
Basic and diluted net income (loss) per share		$ (0.07)	$ 0.01	$ 0.01	$ 0.54	$ 0.05	$ 0.08	$ 0.01	$ (0.05)	$ 0.68	$ 0.22