GENERAL AND BASIS OF PRESENTATION - Principal customers, total revenues (Details) - Revenue Benchmark - Customer Concentration Risk	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Southern California Public Power Authority
Concentration Risk [Line Items]
Concentration risk (in percentage)	19.70%	21.00%	22.30%	23.80%
Sierra Pacific Power Company And Nevada Power Company
Concentration Risk [Line Items]
Concentration risk (in percentage)	14.70%	15.90%	15.80%	17.90%
Kenya Power and Lighting Co LTD
Concentration Risk [Line Items]
Concentration risk (in percentage)	13.10%	14.40%	12.70%	14.40%