Stock-Based Compensation - Information on stock options outstanding (Details) - USD ($)	12 Months Ended
Jul. 31, 2018	Oct. 31, 2018	Jul. 31, 2017
Options Outstanding	2,747,580	2,747,580	232,218
Weighted Average Exercise Price per Share	$ 5.95		$ 1.46
Options Aggregate Intrinsic Value	$ 1,119,400
Exercise Price 0.11
Options Range of Exercise Price	$ 0.11
Options Outstanding	2,730,000
Weighted Average Exercise Price per Share	$ 0.11
Options Weighted Average Remaining Life (Years)	9 years 10 months
Options Aggregate Intrinsic Value	$ 1,119,400
Exercise Price 30.48
Options Range of Exercise Price	$ 30.48
Options Outstanding	17,850
Weighted Average Exercise Price per Share	$ 30.48
Options Weighted Average Remaining Life (Years)	1 year 4 months
Options Aggregate Intrinsic Value

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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