Net Loss Per Share (Details) - shares	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options and warrants excluded from calculation of diluted net loss per share (shares)	17,078,280	23,494,902
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options and warrants excluded from calculation of diluted net loss per share (shares)	14,845,888	14,959,480
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options and warrants excluded from calculation of diluted net loss per share (shares)	2,232,392	8,535,422