Investment in Equity Securities - Summary of Transactions with Unconsolidated VIE (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Related Party Transaction [Line Items]
Sublease income	$ 687	$ 417	$ 2,106	$ 417
Related Party \| Variable Interest Entity, Not Primary Beneficiary
Related Party Transaction [Line Items]
Sublease income	687	417	2,106	417
Interest income	$ 58	$ 34	$ 169	$ 34

Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details