GOODWILL - Summary of Goodwill by Reportable Segment (Details) $ in Thousands	12 Months Ended
Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 4,532,100	$ 4,522,600
Goodwill, Rounding	3,571,400
Ending Balance	3,571,333	4,532,100
Water Acquisitions
Goodwill [Roll Forward]
Water Acquisitions		9,500
Water Sale and Acquisition, net	(1,200)
Water Goodwill Impairment	(297,000)
Water Goodwill Reclassified as Held for Sale	(662,500)
Electric Distribution
Goodwill [Roll Forward]
Beginning Balance	2,543,600	2,543,600
Ending Balance	2,543,600	2,543,600
Electric Distribution \| Water Acquisitions
Goodwill [Roll Forward]
Water Acquisitions		0
Water Sale and Acquisition, net	0
Water Goodwill Impairment	0
Water Goodwill Reclassified as Held for Sale	0
Electric Transmission
Goodwill [Roll Forward]
Beginning Balance	576,800	576,800
Ending Balance	576,800	576,800
Electric Transmission \| Water Acquisitions
Goodwill [Roll Forward]
Water Acquisitions		0
Water Sale and Acquisition, net	0
Water Goodwill Impairment	0
Water Goodwill Reclassified as Held for Sale	0
Natural Gas Distribution
Goodwill [Roll Forward]
Beginning Balance	451,000	451,000
Ending Balance	451,000	451,000
Natural Gas Distribution \| Water Acquisitions
Goodwill [Roll Forward]
Water Acquisitions		0
Water Sale and Acquisition, net	0
Water Goodwill Impairment	0
Water Goodwill Reclassified as Held for Sale	0
Water Distribution
Goodwill [Roll Forward]
Beginning Balance	960,700	951,200
Water Acquisitions	4,200
Ending Balance	0	960,700
Water Distribution \| Water Acquisitions
Goodwill [Roll Forward]
Water Acquisitions	9,500	$ 9,500
Water Sale and Acquisition, net	(1,200)
Water Goodwill Impairment	(297,000)
Water Goodwill Reclassified as Held for Sale	$ (662,500)

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Goodwill, Rounding

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Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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