Assets Held For Sale - Disposal Groups, Including Discontinued Operations (Details) - Aquarion - Disposal Group, Held-for-Sale, Not Discontinued Operations - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Restricted Cash	$ 5.8
Receivables, Net	14.4
Unbilled Revenues	11.5
Prepayments and Other Current Assets	24.6
Total Current Assets Held for Sale	56.3
Property, Plant and Equipment, Net	1,885.2
Regulatory Assets	51.2
Goodwill	662.5	$ 662.5
Other Long-Term Assets	12.2
Total Long-Term Assets Held for Sale	2,611.1
Accounts Payable	24.2
Other Current Liabilities	28.4
Current Liabilities Held for Sale	52.6
Regulatory Liabilities	132.2
Other Long-Term Liabilities	266.7
Total Long-Term Liabilities Held for Sale	$ 398.9