Net Income (Loss) Per Share - Calculations of 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
Basic:
Net income (loss)	$ (11,628)	$ (14,006)	$ (45,253)	$ 9,965
Weighted average common shares outstanding (in shares)	20,919	20,678	20,892	21,042
Net income (loss) per share (in dollars per share)	$ (0.56)	$ (0.68)	$ (2.17)	$ 0.47
Diluted:
Net income (loss) attributable to parent, diluted	$ (11,628)	$ (14,006)	$ (45,253)	$ 9,965
Number of shares used in basic per share computation (in shares)	20,919	20,678	20,892	21,042
Weighted average common shares outstanding (in shares)	20,919	20,678	20,892	21,418
Net income (loss) per share (in dollars per share)	$ (0.56)	$ (0.68)	$ (2.17)	$ 0.47
Restricted Stock Unit And Performance Stock Unit And Deferred Stock Unit [Member]
Diluted:
Stock options (in shares)	0	0	0	354
Employee stock options [Member]
Diluted:
Stock options (in shares)	0	0	0	22