Loans Receivable And Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019
Loans Receivable [Line Items]
Loan-to-value ratio securing commercial real estate loans, maximum	85.00%
Debt service coverage ratio for commercial real estate loans, minimum	1.15
Loan-to-value ratio securing commercial construction loans, maximum	80.00%
Recorded investment of loans in process of foreclosure	$ 1,600	$ 1,500
Carrying value of residential OREO	512	745
Loans receivable	7,429,207	7,416,747
Doubtful [Member]
Loans Receivable [Line Items]
Loans receivable	$ 0	$ 0

For commercial real estate loans, the minimum acceptable debt service coverage ratio.

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Loan To Value Ratio For Securing Commercial Real Estate Loans Maximum

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For commercial construction loans, the maximum acceptable loan to value ratio

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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.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL49126937-111524

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5162-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4437-111522

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