EARNINGS PER SHARE (EPS) (Details) - shares shares in Thousands	3 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Earnings Per Share [Abstract]
Common shares outstanding (in shares)	56,490	46,909
Unallocated ESOP shares (in shares)	(2,010)	(2,209)
Non-vested restricted stock (in shares)	(3,687)	(3,398)
Impact of weighted average shares (in shares)	(197)	(129)
Weighted average shares outstanding - basic (in shares)	50,596	41,173
Incremental shares from stock based compensation (in shares)	2,596	2,722
Weighted average shares outstanding - diluted (in shares)	53,192	43,895

Weighted Average Number Basic Shares Outstanding Adjustment

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

The shares that, although not legally released, will be released by a future scheduled and committed debt service payment and will be allocated to employees for service rendered in the current accounting period. The ESOP documents typically define the period of service to which the shares relate. ESOP shares are released to compensate employees directly, to settle employer liabilities for other employee benefits, and to replace dividends on allocated shares that are used for debt service.

+ References

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

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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.

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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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