Loans Receivable And Allowance For Credit Losses (Gross Charge-offs) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	$ 1
Year Two	6
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	7	$ 4
One- to Four-Family Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	0
Year Two	0
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	0	0
One- to Four-Family Segment [Member] \| Originated [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	0
Year Two	0
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	0	0
One- to Four-Family Segment [Member] \| Correspondent Purchased [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	0
Year Two	0
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	0	0
One- to Four-Family Segment [Member] \| Bulk Purchased [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	0
Year Two	0
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	0	0
Commercial Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	0
Year Two	0
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	0	0
Commercial Segment [Member] \| Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	0
Year Two	0
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	0
Commercial Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	0
Year Two	0
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	0
Consumer Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	1
Year Two	6
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	7	$ 4
Consumer Segment [Member] \| Home Equity [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	1
Year Two	1
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	2
Consumer Segment [Member] \| Other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Year One	0
Year Two	5
Year Three	0
Year Four	0
Year Five	0
Prior Years	0
Revolving Line of Credit	0
Revolving Line of Credit Converted to Term Loan	0
Total Charge-offs	$ 5

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. 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 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of writeoff of financing receivable originated more than five years before current fiscal year. Excludes net investment in lease.

+ References

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Amount, excluding accrued interest, of writeoff of revolving financing receivable converted to term loan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6A

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Amount, excluding accrued interest, of writeoff of financing receivable originated four years before current fiscal year. Excludes net investment in lease.

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Amount, excluding accrued interest, of writeoff of financing receivable originated three years before current fiscal year. Excludes net investment in lease.

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Amount, excluding accrued interest, of writeoff of financing receivable originated in current fiscal year. Excludes net investment in lease.

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Amount, excluding accrued interest, of writeoff of financing receivable originated two years before current fiscal year. Excludes net investment in lease.

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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479294/326-20-55-79

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