Loans Receivable And Allowance For Credit Losses (Troubled Debt Restructurings On Financing Receivables That Subsequently Defaulted) (Details) $ in Thousands	12 Months Ended
Sep. 30, 2018 USD ($) contract	Sep. 30, 2017 USD ($) contract	Sep. 30, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	30	66	57
Recorded Investment \| $	$ 2,713	$ 5,847	$ 6,052
One- to Four-Family Segment [Member] \| Originated [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	22	46	48
Recorded Investment \| $	$ 1,416	$ 4,561	$ 5,330
One- to Four-Family Segment [Member] \| Correspondent Purchased [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	2	3
Recorded Investment \| $	$ 124	$ 148	$ 548
One- to Four-Family Segment [Member] \| Bulk Purchased [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	3	2	0
Recorded Investment \| $	$ 1,040	$ 698	$ 0
Commercial Segment [Member] \| Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	0	0
Recorded Investment \| $	$ 0	$ 0	$ 0
Commercial Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	0	0
Recorded Investment \| $	$ 0	$ 0	$ 0
Consumer Segment [Member] \| Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	4	16	6
Recorded Investment \| $	$ 133	$ 440	$ 174
Consumer Segment [Member] \| Other [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	0	0
Recorded Investment \| $	$ 0	$ 0	$ 0

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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