GOODWILL - Summary of Goodwill by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Dec. 31, 2024
Goodwill [Roll Forward]
Beginning Balance			$ 3,571,333	$ 4,532,100
Goodwill, Rounding		$ 3,571,400		3,571,400
Ending Balance	$ 4,233,767	3,571,333	4,233,767	3,571,333
Water Acquisitions
Goodwill [Roll Forward]
Sale of Water Unregulated Business and Water Acquisition, net				1,200
Water Goodwill Impairment				(297,000)
Water Goodwill Reclassified from Held for Sale			662,500	(662,500)
Measurement Period Adjustment				(100)
Electric Distribution
Goodwill [Roll Forward]
Beginning Balance			2,543,600	2,543,600
Ending Balance	2,543,600	2,543,600	2,543,600	2,543,600
Electric Distribution | Water Acquisitions
Goodwill [Roll Forward]
Sale of Water Unregulated Business and Water Acquisition, net				0
Water Goodwill Impairment				0
Water Goodwill Reclassified from Held for Sale			0	0
Measurement Period Adjustment				0
Electric Transmission
Goodwill [Roll Forward]
Beginning Balance			576,800	576,800
Ending Balance	576,800	576,800	576,800	576,800
Electric Transmission | Water Acquisitions
Goodwill [Roll Forward]
Sale of Water Unregulated Business and Water Acquisition, net				0
Water Goodwill Impairment				0
Water Goodwill Reclassified from Held for Sale			0	0
Measurement Period Adjustment				0
Natural Gas Distribution
Goodwill [Roll Forward]
Beginning Balance			451,000	451,000
Ending Balance	451,000	451,000	451,000	451,000
Natural Gas Distribution | Water Acquisitions
Goodwill [Roll Forward]
Sale of Water Unregulated Business and Water Acquisition, net				0
Water Goodwill Impairment				0
Water Goodwill Reclassified from Held for Sale			0	0
Measurement Period Adjustment				0
Water Distribution
Goodwill [Roll Forward]
Beginning Balance			0	960,700
Sale of Water Unregulated Business and Water Acquisition, net				5,400
Water Goodwill Impairment	0
Ending Balance	$ 662,400	0	662,400	0
Water Distribution | Water Acquisitions
Goodwill [Roll Forward]
Sale of Water Unregulated Business and Water Acquisition, net				1,200
Water Goodwill Impairment		$ (297,000)
Water Goodwill Reclassified from Held for Sale			$ 662,500	(662,500)
Measurement Period Adjustment				$ (100)