v3.25.4

Investment Securities (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Sep. 30, 2025
Schedule of Available For Sale Securities [Line Items]
Investment securities, available for sale	$ 454,493	$ 520,659
Accrued interest receivable	60,295	62,553
Securities Investment
Schedule of Available For Sale Securities [Line Items]
Accrued interest receivable	1,461	2,556
U.S. government and agency obligations
Schedule of Available For Sale Securities [Line Items]
Investment securities, available for sale	3,949	53,955
U.S. government and agency obligations | Asset Pledged as Collateral | Margin requirement
Schedule of Available For Sale Securities [Line Items]
Investment securities, available for sale	$ 0	$ 50,032

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