STOCK-BASED COMPENSATION - Summary of the Status of Performance Share Units (Details) - Performance Share Units - $ / shares shares in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Shares
Outstanding (in shares)	145	0
Granted (in shares)	259	145
Forfeited (in shares)	(67)	0
Outstanding (in shares)	337	145
Weighted-Average Grant Date Fair Value per Share
Outstanding (in dollars per share)	$ 62.66	$ 0
Granted (in dollars per share)	43.40	62.66
Forfeited (in dollars per share)	46.35	0
Outstanding (in dollars per share)	$ 51.09	$ 62.66

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Topic 718
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-Paragraph 2
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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-Publisher FASB
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-Paragraph 2
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No definition available.

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