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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

No definition available.

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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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STOCK-BASED COMPENSATION - NARRATIVE (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)	2,918,487
Performance Shares, Market Condition Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)	44,965	46,813	33,123
Performance Shares, Subject to Performance Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)	73,561	70,138	48,941
Deferred compensation related to unvested performance shares, period	1 year 8 months 12 days
Performance Shares, Subject to Performance Conditions \| Vesting September 30, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)	44,596
Performance Shares, Subject to Performance Conditions \| Vesting Annually Over Three Year Period Beginning September 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)	28,965
Award vesting period	3 years
Performance Shares, Subject to Performance Conditions \| Vesting September 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)		44,156
Performance Shares, Subject to Performance Conditions \| Vesting Annually Over Three Year Period Beginning September 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)		25,982
Award vesting period		3 years
Performance Shares, Subject to Performance Conditions \| Vesting September 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)			30,473
Performance Shares, Subject to Performance Conditions \| Vesting Annually Over Three Year Period Beginning September 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)			18,468
Award vesting period			3 years
Performance share awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)	192,121	166,091	155,731	130,509
Deferred compensation related to unvested restricted and performance shares	$ 4.4
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)	97,824	101,621	73,486	58,156
Deferred compensation related to unvested restricted and performance shares	$ 1.0
Deferred compensation related to unvested performance shares, period	1 year 9 months 18 days
Restricted Stock \| Vesting Annually Over Three Year Period Beginning October 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)	54,826
Award vesting period	3 years
Restricted Stock \| Vesting Annually Over Three Year Period Beginning October 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)		67,726
Award vesting period		3 years
Restricted Stock \| Vesting Annually Over Three Year Period Beginning October 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)			42,478
Award vesting period			3 years