Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2013

Earnings Per Share [Abstract]

Schedule of the components of the calculations of basic and diluted earnings per share

		Three Months Ended
		March 31, 2013		March 31, 2012
Numerator:
	Net loss	$	(8,576,379)	$	(6,583,102)
Denominator:
	Weighted average number of common shares
	outstanding	48,566,794		23,437,600

Schedule of potential dilutive common shares

	At March 31,
	2013			2012
Stock options outstanding		1,986,255		1,948,124
Unvested restricted stock			-	280,771
Common stock warrants (1)		39,662,889		9,421,008
Number of dilutive potential common shares		41,649,144		11,649,903

⁽¹⁾ On May 31, 2011, the Company issued 7,128,563 warrants as part of an underwritten public offering. As a result of the March 28 and 29, 2012 and February 20 and 21, 2013 public offerings described in Note 5, the number of warrants increased to 18,925,389. Additionally, on February 20, 2013 the Company issued 23,637,500 warrants as part of an underwritten public offering. Of the warrants issued in February 2013, 2,900,000 were exercised as of March 31, 2013.