Loans Receivable And Allowance For Credit Losses (Loans, Nonaccrual) (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	$ 10,166	$ 9,453
Nonaccrual loans with no ACL	3,010	1,990
One- to Four-Family Segment [Member] \| Originated [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	2,271	2,457
Nonaccrual loans with no ACL	764	471
One- to Four-Family Segment [Member] \| Correspondent Purchased [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	4,090	3,739
Nonaccrual loans with no ACL	182	285
One- to Four-Family Segment [Member] \| Bulk Purchased [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,539	942
Nonaccrual loans with no ACL	812	630
Commercial Segment [Member] \| Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,495	1,984
Nonaccrual loans with no ACL	901	446
Commercial Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	335	218
Nonaccrual loans with no ACL	335	155
Consumer Segment [Member] \| Home Equity [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	338	107
Nonaccrual loans with no ACL	0	3
Consumer Segment [Member] \| Other [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	98	6
Nonaccrual loans with no ACL	$ 16	$ 0

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-14

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
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-Name Accounting Standards Codification
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-Publisher FASB
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