Stockholders Equity (SBC) (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Stock-based compensation
Stock-based compensation expense	$ (28,713)	$ 1,411,731	$ 1,463,647	$ 4,325,575
Research and development
Stock-based compensation
Stock-based compensation expense	22,112	385,376	86,751	1,202,335
General and administrative
Stock-based compensation
Stock-based compensation expense	(50,825)	1,026,355	1,376,896	3,123,240
Options awards
Stock-based compensation
Stock-based compensation expense	$ 532,381	1,214,856	$ 2,192,085	3,776,013
Additional disclosures
Contractual life			6 years 6 months
Shares
Outstanding at the beginning of the period (in shares)			4,020,783
Forfeited (in shares)			(1,652,793)
Outstanding at the end of the period (in shares)	2,367,990		2,367,990		4,020,783
Vested and expected to vest (in shares)	2,363,144		2,363,144
Exercisable (in shares)	2,024,758		2,024,758
Weighted-Average Exercise Price Per Share
Outstanding at beginning of the period (in dollars per share)			$ 5.48
Forfeited (in dollars per share)			5.91
Outstanding at the end of the period (in dollars per share)	$ 5.18		5.18		$ 5.48
Vested and expected to vest at the end of the period (in dollars per share)	5.18		5.18
Exercisable at the end of the period (in dollars per share)	$ 5.14		$ 5.14
Weighted-Average Contractual Life (In Years)
Outstanding at the end of the period			6 years 7 months 6 days		7 years 9 months 18 days
Vested and expected to vest at the end of the period			6 years 7 months 6 days
Exercisable at the end of the period			6 years 6 months
Restricted stock awards
Stock-based compensation
Stock-based compensation expense		$ 196,875		$ 549,562