Deposits and Borrowed Funds (Maturity Of Borrowed Funds and Certificates of Deposit) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Deposits and Borrowed Funds [Abstract]
FHLB Advances Due in 2015	$ 600,000
FHLB Advances Due in 2016	575,000
FHLB Advances Due in 2017	500,000
FHLB Advances Due in 2018	200,000
FHLB Advances Due in 2019	200,000
FHLB Advances Due Thereafter	500,000
FHLB Advances Amount	2,575,000	2,525,000
Repurchase Agreements Due in 2015	20,000
Repurchase Agreements Due in 2016	0
Repurchase Agreements Due in 2017	0
Repurchase Agreements Due in 2018	100,000
Repurchase Agreements Due in 2019	0
Repurchase Agreements Due Thereafter	100,000
Repurchase Agreements Amount	220,000
Certificates of Deposit Due in 2015	1,269,331
Certificates of Deposit Due in 2016	572,363
Certificates of Deposit Due in 2017	351,939
Certificates of Deposit Due in 2018	281,154
Certificates of Deposit Due in 2019	56,827
Certificates of Deposit Due Thereafter	552
Certificates of Deposit Amount	$ 2,532,166

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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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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 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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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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Amount of time deposits maturing in the next fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. 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 time deposits maturing in the third fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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