Warrant Liabilities (Tables)

12 Months Ended

Dec. 31, 2013

Warrant Liabilities [Abstract]

Schedule of weighted-average Assumptions

The following reflects the weighted-average assumptions for each of the periods indicated:

	Year Ended December 31,
	2013			2012			2011
Risk-free interest rate		0.13% - 0.58	%		0.25% - 0.45	%		0.36% - 0.83	%
Expected dividend yield		0	%		0	%		0	%
Expected lives		0.95 – 2.59			1.95 – 3.59			0.96 – 4.59
Expected volatility		83.4% - 95.3	%		72.6% - 76.0	%		75.0% - 89.8	%
Warrants classified as liabilities (in shares)		6,984,716			6,984,716			7,115,447
(Loss) Gain on warrant liabilities	$	(20,210,094	)	$	2,766,704		$	7,915,027