BANK LOANS, NET, Collateral-dependent loans (Details) - Loans held for investment - USD ($) $ in Millions	Jun. 30, 2025	Sep. 30, 2024
C&I loans \| Commercial real estate and other business assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, gross	$ 14	$ 9
CRE loans \| Hospitality, office, multi-family residential, industrial, healthcare, and medical office real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, gross	128	115
Residential mortgage loans \| Single family homes
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, gross	$ 14	$ 8

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