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FAIR VALUE MEASUREMENT OF FINANCIAL INSTRUMENTS - Narrative (Details) shares in Millions, $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) shares | Sep. 30, 2021 USD ($) shares
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Gain (loss) resulting from the change in the fair value of investments |  | $ 6.7
ADNOC Drilling |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Payments to acquire investments | $ 100.0 |
Investment balance (in shares) | shares | 159.7 | 159.7
Ownership percentage | 1.00% | 1.00%
Investments lockup period | 3 years |

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