Loans Receivable And Allowance For Credit Losses (Troubled Debt Restructurings On Financing Receivables That Subsequently Defaulted) (Details) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2019 USD ($) contract	Mar. 31, 2018 USD ($) contract	Mar. 31, 2019 USD ($) contract	Mar. 31, 2018 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	8	1	27
Recorded Investment \| $	$ 45	$ 558	$ 45	$ 2,551
One- to Four-Family Segment [Member] \| Originated [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	7	1	19
Recorded Investment \| $	$ 45	$ 434	$ 45	$ 1,254
One- to Four-Family Segment [Member] \| Correspondent Purchased [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	1	0	1
Recorded Investment \| $	$ 0	$ 124	$ 0	$ 124
One- to Four-Family Segment [Member] \| Bulk Purchased [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	0	0	3
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 1,040
Commercial Segment [Member] \| Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	0	0	0
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 0
Commercial Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	0	0	0
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 0
Consumer Segment [Member] \| Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	0	0	4
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 133
Consumer Segment [Member] \| Other [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	0	0	0
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 0

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No definition available.

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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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- Definition

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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