Stockholder's Equity - Summary of Warrant Activity (Detail) (Exercise of warrants [Member], USD $)	6 Months Ended
	Jun. 30, 2013
Exercise of warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, Common Stock Warrants, Beginning Balance	395,000
Common Stock Warrants, Granted	50,000
Outstanding, Common Stock Warrants, Ending Balance	445,000
Exercisable, Common Stock Warrants	395,000
Outstanding, Weighted Average Exercise Price, Beginning Balance	$ 5.45
Weighted Average Exercise Price, Granted	$ 7.51
Outstanding, Weighted Average Exercise Price, Ending Balance	$ 5.68
Exercisable, Weighted Average Exercise Price	$ 5.45