Deposits (Summary Of Deposit Account Balances) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Sep. 30, 2019
Time Deposits [Line Items]
Checking accounts	$ 983,308	$ 862,647
Certificates of deposit	6,677,078	6,415,824
Subtotal deposits	9,226,343	8,762,671
Accrued interest	3,768	3,713
Total deposits	9,230,111	8,766,384
Savings Accounts Range excluding MMA
Time Deposits [Line Items]
Savings accounts	1,074,988	1,042,357
Money Market Funds
Time Deposits [Line Items]
Savings accounts	$ 490,969	$ 441,843

Amount of accrued but unpaid interest on deposit liabilities.

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The aggregate of all domestic interest-bearing and noninterest-bearing deposit liabilities.

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Amount of deposits in interest-bearing transaction accounts at banks or savings and loans, that are restricted in regard to ownership and can usually only be held by individuals, nonprofit entities and governments. Negotiable order of withdrawal accounts differ from money market demand accounts as they typically have higher reserve requirements and no limit on the number of checks that can be written.

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Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

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Total amount of interest-bearing domestic deposit liabilities, which may include brokered, retail, demand, checking, notice of withdrawal, money market and other interest-bearing deposits.

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Amount of time deposit liabilities, including certificates of deposit.

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