Loans Receivable And Allowance For Credit Losses (Troubled Debt Restructurings On Financing Receivables) (Details) $ in Thousands	3 Months Ended
Dec. 31, 2019 USD ($) contract	Dec. 31, 2018 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	3	1
Pre-Restructured Outstanding	$ 178	$ 117
Post-Restructured Outstanding	$ 236	$ 117
One- to Four-Family Segment [Member] \| Originated [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	2	1
Pre-Restructured Outstanding	$ 103	$ 117
Post-Restructured Outstanding	$ 102	$ 117
One- to Four-Family Segment [Member] \| Correspondent Purchased [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	0
Pre-Restructured Outstanding	$ 0	$ 0
Post-Restructured Outstanding	$ 0	$ 0
One- to Four-Family Segment [Member] \| Bulk Purchased [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1	0
Pre-Restructured Outstanding	$ 75	$ 0
Post-Restructured Outstanding	$ 134	$ 0
Commercial Segment [Member] \| Commercial Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	0
Pre-Restructured Outstanding	$ 0	$ 0
Post-Restructured Outstanding	$ 0	$ 0
Commercial Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	0
Pre-Restructured Outstanding	$ 0	$ 0
Post-Restructured Outstanding	$ 0	$ 0
Consumer Segment [Member] \| Home Equity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	0
Pre-Restructured Outstanding	$ 0	$ 0
Post-Restructured Outstanding	$ 0	$ 0
Consumer Segment [Member] \| Other [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	0
Pre-Restructured Outstanding	$ 0	$ 0
Post-Restructured Outstanding	$ 0	$ 0

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.

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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