SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Summary of Revenues Disaggregated by Type of Customer) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Disaggregation of Revenue [Abstract]
Total operating revenues	$ 6,188	$ 6,250	$ 18,971	$ 18,131
Electric
Disaggregation of Revenue [Abstract]
Total operating revenues	4,660	4,755	14,015	13,304
Natural gas
Disaggregation of Revenue [Abstract]
Total operating revenues	1,528	1,495	4,956	4,827
Utility
Disaggregation of Revenue [Abstract]
Total operating revenues	6,188	6,250	18,971	18,131
Utility \| Electric
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	5,482	5,848	14,872	14,506
Regulatory balancing accounts	(822)	(1,093)	(857)	(1,202)
Total operating revenues	4,660	4,755	14,015	13,304
Utility \| Electric \| Residential
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	1,980	2,306	5,571	5,561
Utility \| Electric \| Commercial
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	2,365	2,249	5,693	5,368
Utility \| Electric \| Industrial
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	695	655	1,587	1,455
Utility \| Electric \| Agricultural
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	766	807	1,461	1,484
Utility \| Electric \| Public street and highway lighting
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	28	27	81	80
Utility \| Electric \| Other, net
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	(352)	(196)	479	558
Utility \| Natural gas
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	1,065	1,098	3,949	4,593
Regulatory balancing accounts	463	397	1,007	234
Total operating revenues	1,528	1,495	4,956	4,827
Utility \| Natural gas \| Residential
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	468	490	2,303	2,629
Utility \| Natural gas \| Commercial
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	167	173	716	794
Utility \| Natural gas \| Transportation service only
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	385	436	1,249	1,438
Utility \| Natural gas \| Other, net
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	$ 45	$ (1)	$ (319)	$ (268)