COLLATERALIZED AGREEMENTS AND FINANCINGS, Encumbered Assets (Details) - USD ($) $ in Millions	Jun. 30, 2022	Sep. 30, 2021
Federal Home Loan Bank Advances [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Financial instruments, owned, at fair value	$ 8,138	$ 5,716
Had the right to deliver or repledge
Financial Instruments Owned and Pledged as Collateral [Line Items]
Financial instruments, owned, at fair value	422	368
Did not have the right to deliver or repledge
Financial Instruments Owned and Pledged as Collateral [Line Items]
Financial instruments, owned, at fair value	$ 63	$ 65

The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant