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 receivables that have been modified by troubled debt restructurings.

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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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Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default 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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Loans Receivable And Allowance For Credit Losses (Narrative) (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) contracts	Dec. 31, 2024	Sep. 30, 2023 USD ($)
Loans Receivable [Line Items]
Loan-to-value ratio securing commercial real estate loans, maximum	85.00%
Debt service coverage ratio for commercial real estate loans, minimum	1.15
Loan-to-value ratio securing commercial construction loans, maximum	80.00%
Loans receivable	$ 7,947,510			$ 7,970,949
Amortized cost of loans in process of foreclosure	2,800			2,500
Carrying value of residential OREO	444			219
Financing receivable, gross charge-offs on modified loans	0
Financing receivable, modified, commitment to lend	0
Number of contracts, modified \| contracts		0
Off-balance sheet credit exposures	803,000			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
Forecast [Member]
Loans Receivable [Line Items]
Unemployment rate			4.00%
Doubtful [Member]
Loans Receivable [Line Items]
Loans receivable	$ 0			$ 0