FAIR VALUE MEASUREMENT OF FINANCIAL INSTRUMENTS - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended			3 Months Ended		9 Months Ended
	Oct. 31, 2022	Apr. 30, 2022	Sep. 30, 2021	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Mar. 31, 2023	Sep. 30, 2022	Mar. 31, 2022
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				$ (17,000)	$ (17,000)	$ 7,400	$ 47,800
Proceeds from sale of long-term investments						0	22,042
Gain (loss) on investment securities				(18,538)	(14,310)	6,123	$ 55,684
Unrealized gain (loss) on investments				1,600		1,500
Geothermal Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other debt securities				27,400		27,400			$ 23,700
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities				26,300		26,300			23,700
Investments				10,700		10,700			10,700
Convertible Debt | Galileo Technologies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate (as a percent)		5.00%
ADNOC Drilling
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payments to acquire investments			$ 100,000
Investment balance (in shares)			159,700,000
Investments lockup period (in years)			3 years
ADNOC Drilling | ADNOC Drilling
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Ownership percentage (as a percent)			1.00%
Schlumberger, Ltd
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Sale of equity securities, number of shares sold (in shares)							467,500
Proceeds from sale of long-term investments							$ 22,000
Gain (loss) on investment securities					2,700		8,200
Gain (loss) on sale of investment securities					500		500
Gain (loss) on valuation adjustment of investment					2,200		7,700
Tamboran Resources Limited
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payments to acquire investments	$ 14,100
Investment shares acquired (in shares)	106,000,000
Tamboran Resources Limited | Tamboran Resources Limited
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Ownership percentage (as a percent)	6.20%
Galileo Technologies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payments to acquire investments		$ 33,000
Galileo Technologies | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities			$ 500	$ 37,182	$ 36,524	$ 37,182	$ 36,524	$ 35,140	$ 33,565	$ 3,500