STOCK-BASED COMPENSATION - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available to be issued (in shares)	74,718
Share-based Payment Arrangement, Expense	$ 0.7	$ 0.6
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of common shares that may be issued		840,360
Common shares, issuance term		10 years
Shares available to be issued (in shares)	603,869
2010 Plan \| Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period	7 years
Vesting One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Vesting Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	5 years

Share-based Compensation Arrangement by Share-based Payment Award, Issuance Term

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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.

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Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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