Deposits (Summary Of Deposit Account Balances) (Details) - USD ($) $ in Thousands |
Dec. 31, 2025 |
Sep. 30, 2025 |
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| Deposits [Abstract] | ||
| Checking accounts | $ 813,293 | $ 785,785 |
| Savings accounts, excluding money market accounts | 1,443,435 | 1,043,715 |
| Money market accounts | 118,264 | 128,245 |
| Certificates of deposit | 7,980,335 | 8,474,503 |
| Subtotal deposits | 10,355,327 | 10,432,248 |
| Accrued interest | 16,748 | 14,720 |
| Total deposits | $ 10,372,075 | $ 10,446,968 |
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- Definition Interest Bearing Deposit Liabilities Without Accrued Interest Payable No definition available.
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- Definition Amount of accrued but unpaid interest on deposit liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of interest-bearing domestic certificate of deposit liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of interest-bearing domestic checking deposit liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of interest-bearing domestic money market demand account deposit liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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