COMMITMENTS AND CONTINGENCIES Nuclear (Details)	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2014 USD ($)
Forecasted Incremental Capital Costs Associated With Schedule Delays, 2015 Petition	$ 539,000,000
EPC Contract Amendment, New Nuclear Construction Completion Bonus	151,000,000
Aggregate Nominal Coverage of Bond	100,000,000
Aggregate Nominal Coverage of Bond, SCE&G Share	55,000,000
EPC Contract Amendment, Fixed Price Option, Increase In Total New Nuclear Project Cost	$ 774,000,000
Emission Rate Standard For Coal Fired Power Plants Under Clean Air Act	1,400
Goal For Reduced Carbon Dioxide Emissions From 2005 Levels By 2030 Under Clean Air Act	32.00%
Number of States affected by CSAPR	28
Capital costs, owners [Domain]
Forecasted incremental capital costs, 2015 petition	$ 245,000,000
Forecasted Total Capital Costs, 2015 Petition	5,200,000,000.0
Capital costs, Other [Domain] [Domain]
Forecasted incremental capital costs, 2015 petition	453,000,000
Forecasted Total Capital Costs, 2015 Petition	6,800,000,000.0
SCE&G
EPC Contract Amendment, Credit Applied To Target Component Of New Units Contract Price	27,000,000
EPC Contract Amendment, Increase In Fixed Component Of Contract Price	165,000,000
EPC Contract Amendment, Cap On Delay Oriented Liquidated Damages Per New Nuclear Unit	255,000,000
EPC Contract Amendment, Revised Construction Milestone Payment Schedule, Per Month	55,000,000
EPC Contract Amendment, Increase In Total New Nuclear Project Cost	286,000,000
Total New Nuclear Project Cost Approved By SCPSC In September 2015	7,000,000,000
EPC Contract Amendment, Fixed Price Option, Project Cost Including Fixed Option Price Increase	7,600,000,000.0
EPC Contract Amendment, Total New Nuclear Project Cost Including Amendment Increase	7,000,000,000
Aggregate Nominal Coverage of Bond	100,000,000
Aggregate Nominal Coverage of Bond, SCE&G Share	55,000,000
EPC Contract Amendment, Fixed Price Option, Price For New Nuclear Construction After June 2015	3,345,000,000.000
EPC Contract Amendment, Fixed Price Option, Cap On Delay Oriented Liquidated Damages Per New Nuclear Unit	186,000,000
EPC Contract Amendment, Fixed Price Option, New Nuclear Construction Completion Bonus	83,000,000
Summer Station New Units [Domain]
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	3,400,000,000				$ 2,700,000,000
jointly owned utility plant ownership, construction financing cost	3,200,000,000
EPC Contract Amendment, Credit Applied To Target Component Of New Units Contract Price	50,000,000
EPC Contract Amendment, Increase In Fixed Component Of Contract Price	300,000,000
EPC Contract Amendment, Cap On Delay Oriented Liquidated Damages Per New Nuclear Unit	463,000,000
EPC Contract Amendment, New Nuclear Construction Completion Bonus	275,000,000
EPC Contract Amendment, Revised Construction Milestone Payment Schedule, Per Month	100,000,000
EPC Contract Amendment, Fixed Price Option, Price For New Nuclear Construction After June 2015	6,082,000,000.000
EPC Contract Amendment, Fixed Price Option, Cap On Delay Oriented Liquidated Damages Per New Nuclear Unit	338,000,000
EPC Contract Amendment, Fixed Price Option, New Nuclear Construction Completion Bonus	150,000,000
Nuclear Production Tax Credits	1,400,000,000
Scenario, Forecast [Member] | SCE&G
Additional ownership in new units		2.00%	2.00%	1.00%
Minimum [Member] | SCE&G
Additional ownership in new units, dollars	750,000,000
Maximum [Member] | SCE&G
Additional ownership in new units, dollars	$ 850,000,000