Loans Receivable And Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Loans Receivable [Line Items]
Loans receivable, gross	$ 7,224,996	$ 7,412,473
PCI Loans	5
Outstanding discounts	29,190	31,058
Serviced loans for others, aggregate amount	87,200	117,300
Escrow balances on loans serviced for others	$ 1,700	2,200
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	$ 1,500	1,500
Carrying value of residential OREO	183	745
Loans receivable	7,202,851	7,416,747
PCI Loans [Member]
Loans Receivable [Line Items]
Outstanding discounts	5
Non-PCI Loans [Member]
Loans Receivable [Line Items]
Loans receivable, gross	139,600
Outstanding discounts	2,400
Doubtful [Member]
Loans Receivable [Line Items]
Loans receivable	$ 0	$ 0

Aggregate amount of loans serviced by the Bank for others.

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

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Escrow balances held by the Bank on loans serviced for others.

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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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The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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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.

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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.

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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.

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