Shares of Common Stock Reserved for Future Issuance (Detail)	Jun. 30, 2015 shares
Shares Of Common Stock Reserved For Future Issuance [Line Items]
Options to purchase common stock	2,213,963
Shares reserved for issuance	7,432,828
Warrants
Shares Of Common Stock Reserved For Future Issuance [Line Items]
Shares reserved for issuance	1,795,447
2014 Stock Plan
Shares Of Common Stock Reserved For Future Issuance [Line Items]
Shares reserved for issuance	499,217
Series A Convertible Preferred Stock [Member]
Shares Of Common Stock Reserved For Future Issuance [Line Items]
Convertible preferred stock	528,548
Series B Convertible Preferred Stock [Member]
Shares Of Common Stock Reserved For Future Issuance [Line Items]
Convertible preferred stock	2,395,653