Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit) - Summary of Common Stock Reserved for Future Issuance (Detail)	Dec. 31, 2013	Dec. 31, 2012
Class of Stock [Line Items]
Total common stock reserved for future issuance	1,069,250	2,576,252
Conversion of preferred stock [Member]
Class of Stock [Line Items]
Total common stock reserved for future issuance		2,439,002
Stock options issued and outstanding [Member]
Class of Stock [Line Items]
Total common stock reserved for future issuance	624,750	123,250
Authorized for future option grants [Member]
Class of Stock [Line Items]
Total common stock reserved for future issuance	8,500
Warrants for Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Total common stock reserved for future issuance		14,000
Warrants for common stock [Member]
Class of Stock [Line Items]
Total common stock reserved for future issuance	106,000
Authorized for Employee Stock Purchase Plan [Member]
Class of Stock [Line Items]
Total common stock reserved for future issuance	330,000