Net Loss Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Summary of basic and diluted loss per share
Net loss	$ (2,284)	$ (1,723)	$ (7,078)	$ (3,993)	$ (6,939)
Less: Deemed preferred stock dividend				(2,026)	(2,026)
Net loss available to common stockholders	$ (2,284)	$ (1,723)	$ (7,078)	$ (6,019)
Weighted average shares of common stock outstanding	21,029,138	10,835,299	20,282,975	6,302,611
Less: Weighted-average shares of unvested common stock		(2,783)		(2,783)
Total weighted-average shares used in computing net loss per share attributed to common stockholders	21,029,138	10,832,516	20,282,975	6,299,828
Basic and diluted loss per share	$ (0.11)	$ (0.16)	$ (0.35)	$ (0.96)