UTILITY PLANT AND NONUTILITY PROPERTY Jointly Owned Utiltiy Plant (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Utility Plant In Service	$ 15,171.0	$ 14,370.0
Property, Plant and Equipment, Gross	410.0
Electric Generation Equipment [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	5,751.0
Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	16,309.0
Gas Transmission Equipment [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	2,417.0
Electric Distribution [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	6,032.0
Natural Gas, Storage [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	99.0
Other Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	631.0
Other Intangible Assets [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	241.0
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	527.0
Nuclear Fuel [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	611.0
Summer Station Units 1 [Domain]
Property, Plant and Equipment [Line Items]
Accounts Receivable, Net	$ 46.3	$ 53.8
Jointly Owned Utility Plant, Proportionate Ownership Share	67.00%	67.00%
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	$ 1,500.0	$ 1,500.0
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	643.9	637.6
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	127.5	110.1
SCE&G
Property, Plant and Equipment [Line Items]
Utility Plant In Service	12,803.0	$ 12,161.0
SCE&G \| Electric Generation Equipment [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	5,751.0
Property, Plant and Equipment, Gross	73.0
SCE&G \| Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	13,764.0
SCE&G \| Gas Transmission Equipment [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	1,758.0
SCE&G \| Electric Distribution [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	4,456.0
SCE&G \| Natural Gas, Storage [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	74.0
SCE&G \| Other Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	535.0
SCE&G \| Other Intangible Assets [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	229.0
SCE&G \| Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	350.0
SCE&G \| Nuclear Fuel [Member]
Property, Plant and Equipment [Line Items]
Utility Plant In Service	$ 611.0

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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The period end amount owned by the reporting utility of a jointly owned utility plant in service.

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The period end amount of construction work in progress at a jointly owned electricity generation plant.

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The period end amount of accumulated depreciation in a jointly owned electricity generation plant.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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