Loans Receivable And Allowance For Credit Losses (Troubled Debt Restructurings On Financing Receivables) (Details) $ in Thousands	12 Months Ended
Sep. 30, 2023 USD ($) contract	Sep. 30, 2022 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	4	6
Pre-Restructured Outstanding	$ 669	$ 299
Post-Restructured Outstanding	$ 690	$ 299
One- to Four-Family Segment [Member] \| Originated [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1	3
Pre-Restructured Outstanding	$ 110	$ 156
Post-Restructured Outstanding	$ 110	$ 156
One- to Four-Family Segment [Member] \| Correspondent Purchased [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1	0
Pre-Restructured Outstanding	$ 282	$ 0
Post-Restructured Outstanding	$ 285	$ 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	$ 239	$ 0
Post-Restructured Outstanding	$ 257	$ 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	2
Pre-Restructured Outstanding	$ 0	$ 124
Post-Restructured Outstanding	$ 0	$ 124
Consumer Segment [Member] \| Home Equity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1	1
Pre-Restructured Outstanding	$ 38	$ 19
Post-Restructured Outstanding	$ 38	$ 19
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.

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