For commercial real estate loans, the minimum acceptable debt service coverage ratio.

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Loan To Value Ratio For Securing Commercial Real Estate Loans Maximum

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For commercial construction loans, the maximum acceptable loan to value ratio

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Credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, undisbursed portions of loans, or financial guarantee not accounted for as insurance.

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US National Unemployment Rate

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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of increase (decrease) in amortized cost of financing receivable modified for debtor experiencing financial difficulty.

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Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Loans Receivable And Allowance For Credit Losses (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 contracts	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($) contracts	Jun. 30, 2025	Sep. 30, 2023 USD ($)
Loans Receivable [Line Items]
Loan-to-value ratio securing commercial real estate loans, maximum	85.00%		85.00%
Debt service coverage ratio for commercial real estate loans, minimum	1.15		1.15
Loan-to-value ratio securing commercial construction loans, maximum	80.00%		80.00%
Loans receivable	$ 7,933,043		$ 7,933,043			$ 7,970,949
Amortized cost of loans in process of foreclosure	1,900		1,900			2,500
Carrying value of residential OREO	0		0			219
Financing receivable, modified, commitment to lend	0		0
Number of Contracts, modified, subsequent default \| contracts		0
Off-balance sheet credit exposures	754,600		754,600			837,700
One- to Four-Family Segment [Member] \| Originated [Member]
Loans Receivable [Line Items]
Number of Contracts, modified, subsequent default \| contracts				1
Amortized Cost, Modified, Subsequent Default				$ 8
Commercial Segment [Member] \| Commercial Real Estate [Member]
Loans Receivable [Line Items]
Financing receivable, gross charge-offs on modified loans	50		50
Forecast [Member]
Loans Receivable [Line Items]
Unemployment rate					4.10%
Doubtful [Member]
Loans Receivable [Line Items]
Loans receivable	$ 0		$ 0			$ 0