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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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Amount of unamortized loan commitment, origination, and other costs (fees) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Loans Receivable And Allowance For Credit Losses (Summary Of Loans Receivable) (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Loans Receivable [Line Items]
Loans receivable, gross	$ 7,923,251	$ 7,984,381
ACL	23,035	23,759	$ 16,371	$ 19,823
Deferred loan fees/discounts	30,336	31,335
Premiums/deferred costs	(37,458)	(41,662)
Loans receivable, net	7,907,338	7,970,949
One- to Four-Family Segment [Member]
Loans Receivable [Line Items]
Loans receivable, gross	6,304,670	6,591,915
ACL	3,673	5,328	5,006	3,978
One- to Four-Family Segment [Member] \| Originated [Member]
Loans Receivable [Line Items]
Loans receivable, gross	3,941,952	3,978,837
ACL	1,666	2,149	2,066	1,612
One- to Four-Family Segment [Member] \| Correspondent Purchased [Member]
Loans Receivable [Line Items]
Loans receivable, gross	2,212,587	2,405,911
ACL	1,861	2,972	2,734	2,062
One- to Four-Family Segment [Member] \| Bulk Purchased [Member]
Loans Receivable [Line Items]
Loans receivable, gross	127,161	137,193
ACL	146	207	206	304
One- to Four-Family Segment [Member] \| Construction [Member]
Loans Receivable [Line Items]
Loans receivable, gross	22,970	69,974
Commercial Segment [Member]
Loans Receivable [Line Items]
Loans receivable, gross	1,508,978	1,287,487
ACL	19,154	18,180	11,120	15,652
Commercial Segment [Member] \| Construction [Member]
Loans Receivable [Line Items]
Loans receivable, gross	187,676	178,746
Commercial Segment [Member] \| Commercial Real Estate [Member]
Loans Receivable [Line Items]
Loans receivable, gross	1,191,624	995,788
Commercial Segment [Member] \| Commercial and Industrial [Member]
Loans Receivable [Line Items]
Loans receivable, gross	129,678	112,953
Consumer Segment [Member]
Loans Receivable [Line Items]
Loans receivable, gross	109,603	104,979
ACL	208	251	$ 245	$ 193
Consumer Segment [Member] \| Home Equity [Member]
Loans Receivable [Line Items]
Loans receivable, gross	99,988	95,723
Consumer Segment [Member] \| Other [Member]
Loans Receivable [Line Items]
Loans receivable, gross	$ 9,615	$ 9,256