Stockholders' Equity - Schedule of Shares of Common Stock Reserved for Future Issuance (Details) - shares	Sep. 30, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	3,963,829	3,336,378
Employee Stock [Member]
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	321,309	155,220
Stock Options Outstanding [Member]
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	2,307,967	1,907,091
Future Stock Grants [Member]
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	1,334,553	1,274,067