Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

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

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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.

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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	1 Months Ended	12 Months Ended
	Apr. 30, 2019	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)		3,102,764
Performance Shares, Market Condition Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)		46,813	33,123	36,392
Performance Shares, Subject to Performance Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)		70,138	48,941	63,870
Deferred compensation related to unvested performance shares, period		1 year 9 months 18 days
Performance share awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)		166,091	155,731	130,509	145,176
Deferred compensation related to unvested restricted and performance shares		$ 3.9
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)		101,621	73,486	58,156	44,168
Deferred compensation related to unvested restricted and performance shares		$ 1.1
Deferred compensation related to unvested performance shares, period		1 year 9 months 18 days
Vesting September 30, 2022 \| Performance Shares, Subject to Performance Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)		44,156
Vesting Annually Over Three Year Period Beginning September 2020 \| Performance Shares, Subject to Performance Conditions
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
Vesting September 30, 2021 \| Performance Shares, Subject to Performance Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)			30,473
Vesting Annually Over Three Year Period Beginning September 30, 2019 \| Performance Shares, Subject to Performance Conditions
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
Vesting September 30, 2020 \| Performance Shares, Subject to Performance Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)				33,844
Vesting Annually Over Three Year Period Beginning September 30, 2018 \| Performance Shares, Subject to Performance Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)				30,026
Award vesting period				3 years
Vesting Annually Over Three Year Period Beginning October 2020 \| Restricted Stock
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
Vesting Annually Over Three Year Period Beginning October 2019 \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)			42,478	29,222
Award vesting period			3 years	3 years
Vesting Annually Over Three Year Period Beginning April 2020 \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted but not issued (in shares)	6,062
Award vesting period	3 years