Loans Receivable And Allowance For Credit Losses (Loans, Nonaccrual) (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Sep. 30, 2021
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	$ 8,680	$ 13,493
Nonaccrual loans with no ACL	2,726	4,763
One- to Four-Family Segment [Member] \| Originated [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	2,787	4,965
Nonaccrual loans with no ACL	897	2,237
One- to Four-Family Segment [Member] \| Correspondent Purchased [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	2,696	3,257
Nonaccrual loans with no ACL	307	307
One- to Four-Family Segment [Member] \| Bulk Purchased [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,817	3,134
Nonaccrual loans with no ACL	939	1,564
Commercial Segment [Member] \| Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,074	1,496
Nonaccrual loans with no ACL	451	485
Commercial Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	113	134
Nonaccrual loans with no ACL	113	86
Consumer Segment [Member] \| Home Equity [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	193	494
Nonaccrual loans with no ACL	19	84
Consumer Segment [Member] \| Other [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	0	13
Nonaccrual loans with no ACL	$ 0	$ 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

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- Definition

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+ References

No definition available.

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