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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