Condensed Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Convertible preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Convertible preferred stock, shares authorized	10,000,000	10,000,000
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	9,970,538	3,357,390
Common stock, shares outstanding	9,970,538	3,357,390
Series B Convertible Preferred Stock [Member]
Convertible preferred stock, shares designated	13,780	13,780
Convertible preferred stock, shares issued	10,049	12,780
Convertible preferred stock, shares outstanding	10,049	12,780
Convertible preferred stock, aggregate liquidation preference	$ 0	$ 0