Borrowed Funds (Schedule of Federal Home Loan Bank Advances (FHLB) Borrowings) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Advances from Federal Home Loan Banks [Abstract]
Maturing in 12 months or less	$ 3,514,917
Maturing in 13 to 24 months	390
Maturing in 25 to 36 months	1,657
Maturing in 37 to 48 months	265,000
Maturing in 49 to 60 months	275,000
Over 60 months	20,010
Total FHLB Advances	4,076,974
Accrued interest	5,977
Total	$ 4,082,951	$ 3,902,981
Weighted Average Rate: 12 months or less	1.12%
Weighted Average Rate: 13 to 24 months	1.43%
Weighted Average Rate: 25 to 36 months	0.96%
Weighted Average Rate: 37 to 48 months	1.77%
Weighted Average Rate: 49 to 60 months	1.69%
Weighted Average Rate: Over 60 months	1.67%
Weighted Average Rate Total FHLB Advances	1.20%

Concept represents the sum of Federal home Loan Bank advances, excluding related accrued interest.

No definition available.

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- Definition

This element represent the amount of accrued interest due the Federal Home Loan Bank on advances.

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- Definition

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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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due after five years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from four to five years of the Balance Sheet date.

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- Definition

The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due within one year of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from one to two years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from three to four years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from two to three years of the Balance Sheet date.

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- Definition

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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