Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Apr. 30, 2017	Oct. 31, 2016
Statement Of Financial Position [Abstract]
Preferred Stock, Liquidation Preference, Value	$ 64,020	$ 64,020
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	125,000,000	75,000,000
Common stock, shares issued	47,575,606	35,174,424
Common stock, shares outstanding	47,575,606	35,174,424
Treasury stock, shares	88,861	21,527