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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- Definition

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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- Definition

Outstanding Loan Balance for Commercial Total Relationship Annual Review Minimum

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US National Unemployment Rate

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

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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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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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Loans Receivable And Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2027	Sep. 30, 2025
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%
Outstanding Loan Balance for Commercial Total Relationship Annual Review Minimum	$ 2,500
Loans receivable	8,114,205			$ 8,111,961
Amortized cost of loans in process of foreclosure	1,300			1,000
Carrying value of residential OREO	135			197
Financing receivable, gross charge-offs on modified loans		$ 0
Financing Receivable, Modified, Commitment to Lend	0	$ 0
Off-balance sheet credit exposures	896,500			821,600
One- to Four-Family Segment [Member] \| Originated [Member]
Loans Receivable [Line Items]
Financing receivable, gross charge-offs on modified loans	12
Forecast [Member]
Loans Receivable [Line Items]
Unemployment Rate			4.70%
Doubtful [Member]
Loans Receivable [Line Items]
Loans receivable	$ 0			$ 0