The Company and Basis of Presentation (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	12 Months Ended		0 Months Ended
	Jun. 11, 2013	Dec. 31, 2014	Dec. 31, 2013	Jul. 11, 2013	Jul. 02, 2013	Jul. 11, 2013	Dec. 31, 2012	Dec. 31, 2010	Jun. 30, 2014
Reverse Stock Split
Reverse stock split ratio of outstanding common stock	0.1431	0.1431
Par value of common stock (in dollars per share)	$ 0.001	$ 0.001	0.001				$ 0.001	$ 0.001
Common stock | Warrant
Initial Public Offering
Warrants exercisable into common stock (in shares)					277,690				8,230
Series A preferred stock
Initial Public Offering
Number of shares of convertible preferred stock converted into common stock			(57,598,092)
Series A-1 preferred stock
Initial Public Offering
Number of shares of convertible preferred stock converted into common stock			(6,750,000)
Initial Public Offering
Initial Public Offering
Original issue price (in dollars per share)					$ 14.00
Net proceeds from the IPO, including proceeds from the exercise of the underwriters' over-allotment option				$ 72.2
Initial Public Offering | Common stock
Initial Public Offering
Common stock sold (in shares)					5,000,000
Number of shares of convertible preferred stock converted into common stock					9,210,999
Initial Public Offering | Common stock | Additional paid-in capital
Initial Public Offering
Reclassification of convertible preferred stock warrant liability to additional paid-in capital					$ 2.9
Initial Public Offering | Series A preferred stock
Initial Public Offering
Number of shares of convertible preferred stock converted into common stock					8,244,781
Initial Public Offering | Series A-1 preferred stock
Initial Public Offering
Number of shares of convertible preferred stock converted into common stock					966,218
Over-allotment option
Initial Public Offering
Common stock sold (in shares)				750,000		750,000
Original issue price (in dollars per share)				$ 14.00