The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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STOCK-BASED COMPENSATION - Fair Value Assumptions (Details) - $ / shares	9 Months Ended
	Jun. 30, 2018	Sep. 01, 2017	Aug. 31, 2017	Feb. 28, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price (in dollars per share)		$ 4.00	$ 4.00	$ 2.10
1 Year \| Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price (in dollars per share)	$ 0.85
Expected life (years)	5 years 6 months
Expected volatility	82.40%
Expected dividend yield	0.00%
Risk-free interest rate	1.57%
1 Year \| Non-Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price (in dollars per share)	$ 1.10
Expected life (years)	5 years 6 months
Expected volatility	100.80%
Expected dividend yield	0.00%
Risk-free interest rate	2.66%
2 Years \| Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price (in dollars per share)	$ 0.85
Expected life (years)	5 years 9 months
Expected volatility	82.20%
Expected dividend yield	0.00%
Risk-free interest rate	1.57%
2 Years \| Non-Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price (in dollars per share)	$ 1.10
Expected life (years)	5 years 9 months
Expected volatility	102.30%
Expected dividend yield	0.00%
Risk-free interest rate	2.67%
3 Years \| Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price (in dollars per share)	$ 0.85
Expected life (years)	6 years
Expected volatility	81.90%
Expected dividend yield	0.00%
Risk-free interest rate	1.57%
3 Years \| Non-Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price (in dollars per share)	$ 1.10
Expected life (years)	6 years
Expected volatility	103.50%
Expected dividend yield	0.00%
Risk-free interest rate	2.68%
4Years \| Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Price (in dollars per share)	$ 0.85
Expected life (years)	6 years 3 months
Expected volatility	81.70%
Expected dividend yield	0.00%
Risk-free interest rate	1.57%