FAIR VALUES OF FINANCIAL INSTRUMENTS - Assets Measured at Fair Value on Recurring and Non-recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023
Level 1
Debt securities AFS
Total debt securities AFS	$ 0	$ 0
Common equities and mutual funds	3,303	3,378
Level 2
Debt securities AFS
Total debt securities AFS	1,741,221	1,804,228
Common equities and mutual funds	0	0
Level 3
Debt securities AFS
Total debt securities AFS	0	0
Common equities and mutual funds	0	0
Recurring
Debt securities AFS
Corporate securities	19,750	18,250
SBA securities	81,935	85,242
Obligations of states and political subdivisions	480	2,289
Non-bank qualified obligations of states and political subdivisions	217,990	226,723
Asset-backed securities	189,698	246,199
Mortgage-backed securities	1,231,368	1,225,525
Total debt securities AFS	1,741,221	1,804,228
Common equities and mutual funds	3,303	3,378
Non-marketable equity securities	11,828	8,389
Recurring \| Level 1
Debt securities AFS
Corporate securities	0	0
SBA securities	0	0
Obligations of states and political subdivisions	0	0
Non-bank qualified obligations of states and political subdivisions	0	0
Asset-backed securities	0	0
Mortgage-backed securities	0	0
Total debt securities AFS	0	0
Common equities and mutual funds	3,303	3,378
Non-marketable equity securities	0	0
Recurring \| Level 2
Debt securities AFS
Corporate securities	19,750	18,250
SBA securities	81,935	85,242
Obligations of states and political subdivisions	480	2,289
Non-bank qualified obligations of states and political subdivisions	217,990	226,723
Asset-backed securities	189,698	246,199
Mortgage-backed securities	1,231,368	1,225,525
Total debt securities AFS	1,741,221	1,804,228
Common equities and mutual funds	0	0
Non-marketable equity securities	0	0
Recurring \| Level 3
Debt securities AFS
Corporate securities	0	0
SBA securities	0	0
Obligations of states and political subdivisions	0	0
Non-bank qualified obligations of states and political subdivisions	0	0
Asset-backed securities	0	0
Mortgage-backed securities	0	0
Total debt securities AFS	0	0
Common equities and mutual funds	0	0
Non-marketable equity securities	$ 0	$ 0

Fair value of asset backed securities investments classified as available for sale.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents common equities and mutual funds as of the balance sheet date which have been categorized as available-for-sale.

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Corporate Securities Available For Sale

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

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