EARNINGS PER SHARE (Details) - shares	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share [Abstract]
Common shares outstanding (in shares)	46,346,000	48,303,000	53,062,000
Unallocated ESOP shares (in shares)	0	(17,852)	(196,000)
Non-vested restricted stock (in shares)	(1,593,000)	(2,336,000)	(3,111,000)
Impact of weighted average shares (in shares)	601,000	1,624,000	2,356,000
Weighted average shares outstanding - basic (in shares)	45,354,000	47,573,000	52,111,000
Incremental shares from stock based compensation (in shares)	1,331,000	2,095,000	2,501,000
Weighted average shares outstanding - diluted (in shares)	46,685,000	49,668,000	54,612,000

Weighted Average Number Basic Shares Outstanding Adjustment

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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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.

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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.

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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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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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