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FAIR VALUE MEASUREMENT OF FINANCIAL INSTRUMENTS - Level 3 Unobservable Inputs (Details) - Investment in Galileo, net - Level 3 $ in Thousands	Sep. 30, 2025	Sep. 30, 2024 USD ($)
Discount rate
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Inputs	0.187
Risk-free rate
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Inputs	0.035
Equity volatility
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Inputs	0.660
Recurring Fair Value Measurements
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt securities, investment		$ 27,044

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