BANK LOANS, NET, Collateral-dependent loans (Details) - Total loans held for investment - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023
C&I loans \| Commercial real estate and other business assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, gross	$ 9	$ 11
CRE loans \| Office, multi-family residential, healthcare, medical office, and industrial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, gross	115	47
Residential mortgage loans \| Single family homes
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, gross	$ 8	$ 5

Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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+ Details