Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2016

Fair Value, Option, Quantitative Disclosures [Line Items]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The following table represents the Company’s fair value hierarchy for its financial assets and liabilities measured at fair value on a recurring basis:

	As of September 30, 2016
	Level 1		Level 2		Level 3		Balance
Financial Assets
Cash equivalents	$	13,899,719	$	54,964,977	$	-	$	68,864,696
Short-term investments		-		66,841,690		-		66,841,690
Total financial assets measured at fair value	$	13,899,719	$	121,806,667	$	-	$	135,706,386
Financial Liabilities
Current portion of derivative instruments related to stock purchase warrants	$	-	$	-	$	1,150,845	$	1,150,845
Total financial liabilities measured at fair value	$	-	$	-	$	1,150,845	$	1,150,845

	As of December 31, 2015
	Level 1		Level 2		Level 3		Balance
Financial Assets
Cash equivalents	$	6,430,561	$	-	$	-	$	6,430,561
Total financial assets measured at fair value	$	6,430,561	$	-	$	-	$	6,430,561
Financial Liabilities
Current portion of derivative instruments related to stock purchase warrants	$	-	$	-	$	16,411	$	16,411
Non-current portion of derivative instruments related to stock purchase warrants		-		-		491,791		491,791
Total financial liabilities measured at fair value	$	-	$	-	$	508,202	$	508,202

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

The following table sets forth a summary of changes in the fair value of the Company’s Level 3 liabilities for the nine months ended September 30, 2016 and 2015:

	Balance as of		Unrealized		Balance as of
	December 31,		Losses (Gains)		September 30,
Description	2015		2016		2016
Derivative liabilities related to stock purchase warrants	$	508,202	$	642,643	$	1,150,845

	Balance as of		Unrealized		Balance as of
	December 31,		Losses (Gains)		September 30,
Description	2014		2015		2015
Derivative liabilities related to stock purchase warrants	$	807,679	$	(577,426)	$	230,253

Fair Value Inputs, Liabilities, Quantitative Information [Table Text Block]

Quantitative Information about Level 3 Fair Value Measurements
Fair Value at September 30, 2016		Valuation  Technique	Unobservable Inputs
$	1,150,845	Black-Scholes option pricing model	Expected term
			Expected dividends
			Anticipated volatility