Derivative Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2014

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis

The following table summarizes assets and liabilities measured at fair value on a recurring basis at March 31, 2014 and December 31, 2013, respectively:

	March 31, 2014								December 31, 2013
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Fair Value
Measurements Using:
Liabilities
Derivative liabilities- free standing warrants	$	—	$	7,470,271	$	—	$	7,470,271	$	—	$	4,315,183	$	—	$	4,315,183

Reconciliation of Beginning and Ending Balances of Assets and Liabilities Measured at Fair Value Using Significant Observable Inputs

The table below provides a reconciliation of the beginning and ending balances for the liabilities measured at fair value using observable inputs (Level 2). The table reflects net gains and losses for all financial liabilities categorized as Level 2 as of March 31, 2014 and December 31, 2013.

	$			Number of Warrants
Liabilities:
Warrant liability as of December 31, 2013	$	4,315,183			1,999,436
Decrease due to exercise of warrants		(1,670,370	)		(515,000	)
Increase in fair value of warrants		4,825,458			—
Warrant liability as of March 31, 2014	$	7,470,271			1,484,436