SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Summary of Revenues Disaggregated by Type of Customer) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue [Abstract]
Total operating revenues	$ 5,902	$ 5,898	$ 12,783	$ 11,881
Electric
Disaggregation of Revenue [Abstract]
Total operating revenues	4,388	4,414	9,355	8,549
Natural gas
Disaggregation of Revenue [Abstract]
Total operating revenues	1,514	1,484	3,428	3,332
Utility
Disaggregation of Revenue [Abstract]
Total operating revenues	5,902	5,898	12,783	11,881
Utility \| Electric
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	5,029	4,589	9,390	8,658
Regulatory balancing accounts	(641)	(175)	(35)	(109)
Total operating revenues	4,388	4,414	9,355	8,549
Utility \| Electric \| Residential
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	1,784	1,421	3,591	3,255
Utility \| Electric \| Commercial
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	1,736	1,613	3,328	3,119
Utility \| Electric \| Industrial
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	454	386	892	800
Utility \| Electric \| Agricultural
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	490	478	695	677
Utility \| Electric \| Public street and highway lighting
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	27	26	53	53
Utility \| Electric \| Other, net
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	538	665	831	754
Utility \| Natural gas
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	868	961	2,884	3,495
Regulatory balancing accounts	646	523	544	(163)
Total operating revenues	1,514	1,484	3,428	3,332
Utility \| Natural gas \| Residential
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	355	430	1,835	2,139
Utility \| Natural gas \| Commercial
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	181	222	549	621
Utility \| Natural gas \| Transportation service only
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	374	456	864	1,002
Utility \| Natural gas \| Other, net
Disaggregation of Revenue [Abstract]
Total revenue from contracts with customers	$ (42)	$ (147)	$ (364)	$ (267)