Convertible Preferred Stock and Detachable Warrants (Details) (USD $)	1 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended
	Apr. 30, 2014	Jun. 30, 2013	Sep. 30, 2014	Sep. 30, 2014	Dec. 31, 2013
Convertible preferred stock
Convertible preferred stock, shares authorized					52,953,684
Stock issuance costs				4,861,814
Common stock issued upon conversion of shares (in shares)			7,661,871
Series C Convertible Notes
Convertible preferred stock
Amount of convertible notes including accrued interest converted into shares		2,761,019
Amount of accrued interest converted into shares		461,019
Series A Preferred Stock
Convertible preferred stock
Convertible preferred stock, shares authorized					18,777,860
Series B Preferred Stock
Convertible preferred stock
Convertible preferred stock, shares authorized					15,275,824
Series C Preferred Stock
Convertible preferred stock
Convertible preferred stock, shares authorized					18,900,000
Shares issued (in shares)	422,119	6,396,065		422,119
Share price (in dollars per share)		$ 1.1845
Proceeds from shares issued		7,530,335			500,000
Stock issuance costs		$ 45,804
Shares issued upon conversion of convertible notes (in shares)		2,330,955
Common stock issued upon conversion of shares (in shares)			220
Preferred Stock [Member]
Convertible preferred stock
Convertible preferred stock, shares authorized			25,000,000	25,000,000