Warrant Liabilities (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Derivative [Line Items]
Gain (loss) on warrant liability	$ (1,871,294)	$ 14,702,904
Warrants [Member]
Derivative [Line Items]
Risk-free interest rate (in hundredths)	0.41%	0.63%
Expected dividend yield (in hundredths)	0.00%	0.00%
Expected lives	1 year 4 months 2 days	2 years 2 months 16 days
Expected volatility (in hundredths)	92.40%	85.70%
Warrants classified as liabilities (in shares)	6,371,854	6,984,716
Gain (loss) on warrant liability	$ (1,871,294)	$ 14,702,904