Stockholders' Equity - Summary of Warrants Outstanding to Purchase Common Stock (Detail) (USD $)			6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 $0.01 - 5.00 [Member]	Jun. 30, 2014 Midcap warrant [Member] $0.01 - 5.00 [Member]
Warrants, by Exercise Price Range [Line Items]
Range of Exercise Prices, minimum			$ 0.01
Range of Exercise Prices, maximum			$ 5.00
Number Outstanding	3,363,406	4,192,927		1,379,244
Weighted Average Remaining Contractual Life (Years)				1 year 2 months 23 days
Weighted Average Exercise Price	$ 4.15	$ 3.82		$ 3.26
Aggregate Intrinsic Value	$ 26,639,362			$ 12,151,262