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Mergers, Acquisitions and Divestitures - Narrative (Details) $ in Millions			3 Months Ended		6 Months Ended
	Jun. 01, 2026 USD ($) customer employee	Oct. 26, 2025 Rate	Jun. 30, 2026 USD ($) customer	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) acquisition customer	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)	Dec. 09, 2021 USD ($)
Business Combination [Line Items]
Aggregate purchase price	$ 319				$ 27
Number of customers in service \| customer	47,000		5,700		5,700
Number of employees \| employee	70
Number of acquisitions \| acquisition					3
Assets acquired					$ 35
Liabilities assumed			$ 8		$ 8
Number of business combination and asset acquisition acquired \| acquisition					1
Interest income			3	$ 22	$ 15	$ 44
Disposal Group, Disposed of by Sale \| Homeowner Services Group
Business Combination [Line Items]
Consideration								$ 1,275
Interest income			0	$ 20	9	$ 40
Disposal Group, Disposed of by Sale \| Homeowner Services Group \| Secured Seller Promissory Note
Business Combination [Line Items]
Debt instrument, face amount							$ 795
Interest rate							10.00%
Essential Utilities, Inc.
Business Combination [Line Items]
Merger transaction, share exchange ratio \| Rate		30.50%
Merger related costs			$ 4		$ 9