Stock-Based Compensation - Common stock options granted, forfeited or expired and exercised (Details) - USD ($)	3 Months Ended	12 Months Ended
Oct. 31, 2019	Jul. 31, 2019
Share-based Payment Arrangement [Abstract]
Options Outstanding, Beginning	7,988,675
Options Granted	1,003,000
Options Forfeited or expired	(130,000)
Options Exercised	0
Options Outstanding, End	8,861,675	7,988,675
Weighted Average Exercise Price per Share, Beginning	$ 0.84
Weighted Average Exercise Price per Share, Granted	2.09
Weighted Average Exercise Price per Share, Forfeited or expired	1.11
Weighted Average Exercise Price per Share, Exercised
Weighted Average Exercise Price per Share, End	$ 0.98	$ 0.84
Weighted Average Remaining Life Options Outstanding (Years)	6 years 8 months 16 days	7 years 2 months 16 days
Weighted Average Remaining Life Options Granted	4 years 11 months 1 day
Weighted Average Remaining Life Options Forfeited or expired	7 years 7 months 24 days
Aggregate Intrinsic Value Options, Outstanding Beginning	$ 15,961,391
Aggregate Intrinsic Value Options Granted
Aggregate Intrinsic Value Options, Outstanding Ending	$ 5,859,392	$ 15,961,391

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- Definition

Number of non-option equity instruments exercised by participants.

+ 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
-Subparagraph (c)(1)(iv)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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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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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Gross number of share options (or share units) granted during the period.

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

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

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

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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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