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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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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
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Balance held at close of period in number of shares.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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