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JUNIOR SUBORDINATED DEFERRABLE INTEREST DEBENTURES - Narrative (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2025 USD ($) company
Debt Instrument [Line Items]
Number of wholly-owned trust companies | company	2
Equity securities	$ 35,564
Interest deferment period (not exceeding)	5 years
Trust securities
Debt Instrument [Line Items]
Equity securities	$ 1,900

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