Deposits and Borrowed Funds (Maturity Of Borrowed Funds and Certificates of Deposit) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Deposits and Borrowed Funds [Abstract]
FHLB Advances Due in 2020	$ 990,000
FHLB Advances Due in 2021	550,000
FHLB Advances Due in 2022	200,000
FHLB Advances Due in 2023	200,000
FHLB Advances Due in 2024	100,000
FHLB Advances Due Thereafter	0
FHLB Advances Amount	2,040,000	$ 2,075,000
Repurchase Agreements Due in 2020	100,000
Repurchase Agreements Due in 2021	0	$ 100,000
Repurchase Agreements Due in 2022	0
Repurchase Agreements Due in 2023	0
Repurchase Agreements Due in 2024	0
Repurchase Agreements Due Thereafter	0
Repurchase Agreements Amount	100,000
Certificates of Deposit Due in 2020	1,505,837
Certificates of Deposit Due in 2021	625,990
Certificates of Deposit Due in 2022	498,352
Certificates of Deposit Due in 2023	303,817
Certificates of Deposit Due in 2024	53,022
Certificates of Deposit Due Thereafter	607
Certificates of Deposit Amount	$ 2,987,625

Deposits and Borrowed Funds [Abstract]

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of interest-bearing domestic certificate of deposit liabilities.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

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