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Property, Plant and Equipment - Schedule of Major Classes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Public Utility, Property, Plant and Equipment [Line Items]
Construction work in progress	$ 1,548	$ 1,359
Total utility plant	37,852	34,918
Nonutility property	103	141
Total property, plant and equipment	37,955	35,059
Utility Plant | Land and other non-depreciable assets
Public Utility, Property, Plant and Equipment [Line Items]
Utility plant excluding construction work in progress	317	302
Utility Plant | Sources of supply
Public Utility, Property, Plant and Equipment [Line Items]
Utility plant excluding construction work in progress	$ 1,252	1,124
Utility Plant | Sources of supply | Minimum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	20 years
Utility Plant | Sources of supply | Maximum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	114 years
Utility Plant | Sources of supply | Weighted Average
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	45 years
Utility Plant | Treatment and pumping
Public Utility, Property, Plant and Equipment [Line Items]
Utility plant excluding construction work in progress	$ 5,093	4,786
Utility Plant | Treatment and pumping | Minimum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	2 years
Utility Plant | Treatment and pumping | Maximum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	119 years
Utility Plant | Treatment and pumping | Weighted Average
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	40 years
Utility Plant | Transmission and distribution
Public Utility, Property, Plant and Equipment [Line Items]
Utility plant excluding construction work in progress	$ 15,807	14,745
Utility Plant | Transmission and distribution | Minimum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	15 years
Utility Plant | Transmission and distribution | Maximum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	128 years
Utility Plant | Transmission and distribution | Weighted Average
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	65 years
Utility Plant | Services, meters and fire hydrants
Public Utility, Property, Plant and Equipment [Line Items]
Utility plant excluding construction work in progress	$ 7,046	6,356
Utility Plant | Services, meters and fire hydrants | Minimum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	2 years
Utility Plant | Services, meters and fire hydrants | Maximum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	109 years
Utility Plant | Services, meters and fire hydrants | Weighted Average
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	28 years
Utility Plant | General structures and equipment
Public Utility, Property, Plant and Equipment [Line Items]
Utility plant excluding construction work in progress	$ 3,116	2,813
Utility Plant | General structures and equipment | Minimum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	2 years
Utility Plant | General structures and equipment | Maximum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	109 years
Utility Plant | General structures and equipment | Weighted Average
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	16 years
Utility Plant | Waste collection
Public Utility, Property, Plant and Equipment [Line Items]
Utility plant excluding construction work in progress	$ 2,124	1,986
Utility Plant | Waste collection | Minimum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	5 years
Utility Plant | Waste collection | Maximum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	145 years
Utility Plant | Waste collection | Weighted Average
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	52 years
Utility Plant | Waste treatment, pumping and disposal
Public Utility, Property, Plant and Equipment [Line Items]
Utility plant excluding construction work in progress	$ 1,530	1,425
Utility Plant | Waste treatment, pumping and disposal | Minimum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	4 years
Utility Plant | Waste treatment, pumping and disposal | Maximum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	165 years
Utility Plant | Waste treatment, pumping and disposal | Weighted Average
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	32 years
Utility Plant | Other plant
Public Utility, Property, Plant and Equipment [Line Items]
Utility plant excluding construction work in progress	$ 19	$ 22
Utility Plant | Other plant | Minimum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	1 year
Utility Plant | Other plant | Maximum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	54 years
Utility Plant | Other plant | Weighted Average
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	18 years
Nonutility Plant | Minimum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	3 years
Nonutility Plant | Maximum
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	50 years
Nonutility Plant | Weighted Average
Public Utility, Property, Plant and Equipment [Line Items]
Useful Life	16 years

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Public non utilities property plant and equipment plant for internal operations.

+ References

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- Definition

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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