Stockholders' Equity (Deficit) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2015

Dec. 31, 2014

Stockholders' Equity [Abstract]

Summary of Activity of Common Stock Warrants Retroactively Adjusted for Reverse Stock Split

	Common Stock Warrants
Outstanding, December 31, 2012		53,159
Granted to underwriters		125,000
Exercised		—
Expired		—
Outstanding, December 31, 2013		178,159
Granted to lenders		52,695
Exercised		(88,462	)
Expired		—
Outstanding, December 31, 2014		142,392

Schedule of Components of Stock-based Compensation Included in Net Loss

	For the years ended
	December 31,
	2014		2013
Employee stock options	$	570,760	$	131,178
Non-employee stock options		495,683		415,212
Restricted stock awards		—		25,534
	$	1,066,443	$	571,924

Schedule of Stock Option Valuation Assumptions

Dividend yield	0.0	%
Expected volatility	83.62	%
Risk-free interest rate	1.63	%
Expected lives (years)	6.0

	December 31,
	2014			2013
Dividend yield		0.0	%		0.0	%
Expected volatility		107-110	%		90-112	%
Risk-free interest rate		2.06-2.23	%		1.39-2.26	%
Expected lives (years)		5.9-6.5			5.75-6.5

Schedule of Stock Option Activity

	Shares			Weighted Average Exercise Price
Outstanding, December 31, 2014		1,018,590		$	5.04
Granted		277,875		$	6.09
Exercised		(10,272	)	$	1.97
Forfeited		(179,298	)	$	6.50
Outstanding, September 30, 2015		1,106,895		$	5.10

	Shares			Weighted Average Exercise Price
Outstanding, December 31, 2012		590,047		$	0.71
Granted		186,736		$	10.07
Exercised		(80,706	)	$	0.67
Forfeited		(62,595	)	$	1.96
Outstanding, December 31, 2013		633,482		$	3.36
Granted		507,879		$	6.30
Exercised		(78,664	)	$	0.60
Forfeited		(44,107	)	$	3.19
Outstanding, December 31, 2014		1,018,590		$	5.04

Schedule of Options Outstanding, Exercisable, and Vested or Expected to Vest

Options Outstanding					Options Vested and Exercisable
Balance as of 9/30/2015	Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price		Balance as of 9/30/2015		Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price
1,106,895		7.4	$	5.10		649,421		6.2	$	3.89

Options Outstanding			Options Exercisable			Options Vested or Expected to Vest
Balance as of 12/31/2014	Weighted Average Remaining Contractual Life (Years)	Weighted Average Exercise Price	Balance as of 12/31/2014	Weighted Average Remaining Contractual Life (Years)	Weighted Average Exercise Price	Balance as of 12/31/2014	Weighted Average Remaining Contractual Life (Years)	Weighted Average Exercise Price
1,018,590	7.81	$5.04	473,696	5.99	$2.67	473,696	5.99	$2.67