STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION - Summary of stock-based compensation expense (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Stockholders' Equity Note [Abstract]
Restricted stock	$ 18,810	$ 16,410	$ 14,702
ESOP	14,325	3,678	2,878
Total stock based compensation	$ 33,135	$ 20,088	$ 17,580

Amount, after tax, of expense for award under share-based payment arrangement.

No definition available.

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- Definition

The amount of plan compensation cost recognized during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929

+ Details

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- Definition

Amount of noncash expense for award of restricted stock or unit under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

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- References

No definition available.

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