BANK DEPOSITS, Summary of Interest Expense on Deposits (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
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Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
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| Deposits [Abstract] | ||||
| Money market and savings accounts | $ 142 | $ 169 | $ 446 | $ 484 |
| Interest-bearing demand deposits | 212 | 247 | 646 | 742 |
| Certificates of deposit | 19 | 30 | 71 | 92 |
| Total interest expense on deposits | $ 373 | $ 446 | $ 1,163 | $ 1,318 |
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- References No definition available.
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- Definition Aggregate amount of interest expense on all deposits. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of interest expense on domestic checking deposit liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The aggregate interest expense incurred on the following for deposits in domestic offices: (1) transaction accounts (NOW, and telephone and preauthorized transfer accounts), (2) money market deposits and (3) savings deposits. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The aggregate interest expense incurred on time deposits, including certificates of deposits, in domestic offices. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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