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FAIR VALUE MEASUREMENT OF FINANCIAL INSTRUMENTS - Level 3 Unobservable Inputs (Details) $ in Thousands | Jun. 30, 2025 USD ($) | Sep. 30, 2024 USD ($)
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Recurring Fair Value Measurements | Galileo Technologies |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value (in thousands) | $ 38,972 | $ 27,044
Level 3 | Discount rate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Unobservable Inputs | 0.175 | 0.187
Level 3 | Risk-free rate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Unobservable Inputs | 0.040 | 0.035
Level 3 | Equity volatility |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Unobservable Inputs | 0.950 | 0.660
Level 3 | Recurring Fair Value Measurements | Galileo Technologies |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value (in thousands) | $ 38,972 | $ 27,044

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