Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2013 Preferred Stock Series A1	Dec. 31, 2012 Preferred Stock Series A1
Summary Of Significant Accounting Policies [Line Items]
Common stock exchange price	$ 3.30
Convertible preferred stock, liquidation preference		$ 5,616,875	$ 5,420,938
Common stock shares issued upon conversion of Convertible preferred stock	1,698,182