Computation of (Loss) Earnings Per Share - Basic and Diluted EPS (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Basic net income per share:
Net (loss) income	$ (6,908)	$ (1,755)	$ (8,420)	$ 10,612
Less: income allocated to participating securities				(32)
Net income allocated to common stockholders				10,580
Weighted average common shares outstanding — basic	34,347	33,802	34,271	33,658
Net income per share — basic	$ (0.20)	$ (0.05)	$ (0.25)	$ 0.31
Diluted net income per share:
Net (loss) income	(6,908)	(1,755)	(8,420)	10,612
Less: income allocated to participating securities				(31)
Net income allocated to common stockholders				$ 10,581
Weighted average common shares outstanding — basic	34,347	33,802	34,271	33,658
Dilutive securities				1,058
Weighted average common shares outstanding — diluted	34,347	33,802	34,271	34,716
Net income per share — diluted	$ (0.20)	$ (0.05)	$ (0.25)	$ 0.30