BANK DEPOSITS, Summary of Interest Expense on Deposits (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Interest expense on deposits [Abstract]
Savings and money market accounts	$ 11	$ 0	$ 13	$ 2
Interest-bearing checking accounts	6	1	8	2
Certificates of deposit	3	4	10	13
Total interest expense on deposits	$ 20	$ 5	$ 31	$ 17

Aggregate amount of interest expense on all deposits.

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- References

No definition available.

+ Details

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- Definition

Amount of interest expense on domestic checking deposit liabilities.

+ References

+ Details

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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.

+ References

+ Details

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- Definition

The aggregate interest expense incurred on time deposits, including certificates of deposits, in domestic offices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (a)

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (b)
-Subparagraph (1)

+ Details

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