Derivative Instruments (Schedule Of Effect Of Derivative Instruments, Gain (Loss) In Statement Of Financial Performance) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Designated as Hedging Instrument \| Cash Flow Hedge \| Interest expense: Borrowed funds and Deposits
Derivatives, Fair Value [Line Items]
Amount of gain/(loss) reclassified from AOCI	$ 6,581	$ 14,812
Designated as Hedging Instrument \| Cash Flow Hedge \| Other Comprehensive Income (Loss)
Derivatives, Fair Value [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	$ 4,090	$ 76,967
Not Designated as Hedging Instrument \| Interest Rate Lock Commitments
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Noninterest Income, Other Operating Income	Noninterest Income, Other Operating Income
Total	$ (272)	$ (369)
Not Designated as Hedging Instrument \| Forward Commitments For Sale Of Mortgage Loans
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Net gain on the sale of loans	Net gain on the sale of loans
Total	$ 288	$ 70

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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