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Net proceeds from issuance of common stock.

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Percentage of sales commission.

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Adjustment for noncash service expenses paid for by granting of warrants.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of warrants or rights outstanding.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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The cash inflow from the additional capital contribution to the entity.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Stockholders' Equity - Additional Information (Details) - USD ($)					3 Months Ended		9 Months Ended
	Jul. 31, 2019	Feb. 21, 2019	Jun. 13, 2018	May 03, 2017	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Oct. 31, 2018
Stockholders' Equity Note
Sale of common stock, net of fees					$ 16,199,000	$ 6,745,000
Exchange Agreement [Member]
Stockholders' Equity Note
Common stock issued to warrant holders		500,000
Series C Warrants [Member]
Stockholders' Equity Note
Class of Warrant or Right, Outstanding	964,114				964,114		964,114	964,114
Series A Warrants [Member]
Stockholders' Equity Note
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 69.96				$ 69.96		$ 69.96
Class of Warrant or Right, Outstanding	640,000				640,000		640,000
Series A Warrant [Member]
Stockholders' Equity Note
Class of Warrant or Right, Outstanding								640,000
Fair value of the warrant pre-modification							$ 3,169,000
Series A Warrant [Member] \| Exchange Agreement [Member]
Stockholders' Equity Note
Fair value of the warrant pre-modification							300,000
Fair value of the shares at the date of the Exchange Agreement							$ 3,500,000
Common Stock [Member]
Stockholders' Equity Note
Stock issued during period, shares, new issues					43,997,807	435,329
Sale of common stock, net of fees					$ 3,000
Common Stock [Member] \| Series C Warrants [Member]
Stockholders' Equity Note
Stock issued during period, shares, new issues							0
Common Stock [Member] \| Series D Warrants [Member]
Stockholders' Equity Note
Stock issued during period, shares, new issues							0
At Market Issuance Sales Agreement [Member] \| B. Riley FBR, Inc and Oppenheimer & Co. Inc. [Member]
Stockholders' Equity Note
Percentage of sales commission			3.00%
At Market Issuance Sales Agreement [Member] \| Maximum [Member] \| B. Riley FBR, Inc and Oppenheimer & Co. Inc. [Member]
Stockholders' Equity Note
Aggregate offering price			$ 50,000,000
At Market Issuance Sales Agreement [Member] \| Common Stock [Member] \| B. Riley FBR, Inc and Oppenheimer & Co. Inc. [Member]
Stockholders' Equity Note
Stock issued during period, shares, new issues					44,000,000		44,000,000
Average sale price	$ 0.38				$ 0.38		$ 0.38
Stock issued during period on sales agreement							$ 16,700,000
Sales commissions paid to agent					$ 500,000		500,000
Net proceeds on sales agreement					$ 16,200		16,200
Sale of common stock, net of fees							$ 24,700
At Market Issuance Sales Agreement [Member] \| Common Stock [Member] \| Maximum [Member] \| B. Riley FBR, Inc and Oppenheimer & Co. Inc. [Member]
Stockholders' Equity Note
Stock to be sold in future during period value new issues	$ 25,300,000
Underwritten Public Offering [Member]
Stockholders' Equity Note
Stock issued during period, shares, new issues				1,000,000
Underwritten Public Offering [Member] \| Series C Warrants [Member]
Stockholders' Equity Note
Class of warrants or rights issued				1,000,000
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 19.20
Class of warrant or right term				5 years
Underwritten Public Offering [Member] \| Series D Warrants [Member]
Stockholders' Equity Note
Class of warrants or rights issued				1,000,000