SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - ADDITIONAL INFORMATION (Details) $ in Thousands	1 Months Ended	3 Months Ended
	Jul. 31, 2021 Megawatt	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2023 USD ($)
Finite-Lived Intangible Assets [Line Items]
Number of megawatts | Megawatt	5
Operating revenues		$ 467,210	$ 723,567
Loans receivable in other noncurrent assets		41,700		$ 39,000
Financial Asset, Not Past Due
Finite-Lived Intangible Assets [Line Items]
Loans receivable in other current assets		$ 15,600		15,100
Minimum
Finite-Lived Intangible Assets [Line Items]
Loans receivable, term		2 years
Maximum
Finite-Lived Intangible Assets [Line Items]
Loans receivable, term		10 years
ES
Finite-Lived Intangible Assets [Line Items]
Operating revenues		$ 9,500	$ 20,000
Deferred revenue		$ 116,800		$ 58,700