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Property, Plant and Equipment (Regulated and Non-Regulated Assets) (Narrative) (Details) - Pipeline lateral - SeaCoast Gas Transmission, LLC - General plant and other $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2024 mi | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Jointly Owned Pipeline lateral |  |  |
Jointly Owned Utility Plant, Proportionate Ownership Share |  | 50.00% |
Length of pipeline, in miles | mi | 26 |  |
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service |  | $ 27 | $ 27
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation |  | $ 3 | $ 2

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- Definition The period end amount owned by the reporting utility of a jointly owned utility plant in service. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 360 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479070/980-360-S99-1 + Details
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- Definition The period end amount of accumulated depreciation in a jointly owned electricity generation plant. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 360 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479070/980-360-S99-1 + Details
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- Definition The proportionate share of interest (percent) in a jointly owned utility plant. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 360 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479070/980-360-S99-1 + Details
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