Derivative Financial Instruments - Changes in Fair Values of Derivative Liabilities (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Derivative [Line Items]
Total derivative income (expense)	$ (462,903)	$ (182,713)
Senior Convertible Notes [Member]
Derivative [Line Items]
Derivative income (expense)		47,243
2014 Convertible Promissory Notes [Member]
Derivative [Line Items]
Derivative income (expense)	(479,126)
Warrant Derivatives [Member]
Derivative [Line Items]
Derivative income (expense)	$ 16,223	$ (229,956)