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		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Net income (loss)	$ (3,018)	$ 2,120	$ (2,217)	$ 6,100
Weighted average common basic shares	41,041	40,995	41,026	40,981
Effect of dilutive securities		302		304
Weighted average common dilutive shares	41,041	41,297	41,026	41,285
Basic and diluted net income (loss) per share	$ (0.07)	$ 0.05	$ (0.05)	$ 0.15