13. STOCK-BASED COMPENSATION - Schedule of Option Summary (Details) - $ / shares	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Equity [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	1,547,029	277,948	81,254
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 18.35	$ 6.34	$ 11.82
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	1,469,250	233,233
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 19.32	$ 5.28
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period	12,975	25,692
Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price	$ 10.53	$ 8.71
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	45,876	10,847
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 16.31	$ 19.04
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	141,318
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 6.14

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Weighted average price of options that were either forfeited or expired.

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- Definition

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.

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

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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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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Number of share options (or share units) exercised during the current period.

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