SHAREHOLDERS' EQUITY SHAREHOLDERS EQUITY - Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Stockholders' Equity Note [Abstract]
Restricted stock	$ 4,349	$ 3,662	$ 7,777	$ 6,812
ESOP	944	658	1,724	1,490
Total stock based compensation	$ 5,293	$ 4,320	$ 9,501	$ 8,302

The amount of plan compensation cost recognized during the period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (c)
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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
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Amount of noncash expense for 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
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