Net (Loss) Income Per Share - Computation of Basic and Diluted Net (Loss) Income Per Share Attributable to Common Stockholders (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Earnings Per Share [Abstract]
Net (loss) income	$ (3,645)	$ 5,337	$ (7,028)	$ 2,705
Add back: extinguishment of preferred shares				891
Less: net income attributable to participating securities		(3,869)		(2,656)
Net (loss) income attributable to common stockholders - Basic	(3,645)	1,468	(7,028)	940
Add: net income attributable to participating securities		3,869		2,656
Net (loss) income attributable to common stockholders - Diluted	(3,645)	5,337	(7,028)	3,596
Net (loss) income attributable to common stockholders - Basic	$ (3,645)	$ 1,468	$ (7,028)	$ 940
Net (loss) income per share attributable to common stockholders:
Basic	$ (0.16)	$ 0.34	$ (0.37)	$ 0.24
Diluted	$ (0.16)	$ 0.33	$ (0.37)	$ 0.23
Weighted-average common shares outstanding attributable to common stockholders:
Basic	22,608,324	4,288,243	19,150,412	3,975,463
Diluted	22,608,324	15,972,449	19,150,412	15,668,778