Loss Per Share - Calculation of Basic and Diluted Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
		Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Numerator
Net loss		$ (15,881)	$ (17,001)	$ (33,238)	$ (43,924)
Net loss attributable to common stockholders		$ (17,620)	$ (17,801)	$ (44,239)	$ (46,324)
Denominator
Weighted average basic common shares		86,297,481	57,420,050	79,292,240	45,903,033
Effect of dilutive securities	[1]	0	0	0	0
Weighted average diluted common shares		86,297,481	57,420,050	79,292,240	45,903,033
Basic loss per share		$ (0.20)	$ (0.31)	$ (0.56)	$ (1.01)
Diluted loss per share	[1]	$ (0.20)	$ (0.31)	$ (0.56)	$ (1.01)
Series C Preferred Stock [Member]
Numerator
Series C preferred stock deemed dividends		$ (939)	$ 0	$ (8,601)	$ 0
Series B Preferred Stock [Member]
Numerator
Series B preferred stock dividends		$ (800)	$ (800)	$ (2,400)	$ (2,400)

[1] Due to the net loss to common stockholders in each of the periods presented above, diluted loss per share was computed without consideration to potentially dilutive instruments as their inclusion would have been antidilutive.