Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Numerator:
Net loss available for common shareholders - basic and diluted	$ (2,769)	$ (3,401)	$ (6,731)	$ (11,419)
Denominator:
Weighted-average shares outstanding - basic and diluted	46,663	43,015	45,818	38,951
Net loss per share - basic and diluted	$ (0.06)	$ (0.08)	$ (0.15)	$ (0.29)