COMMITMENTS AND CONTINGENCIES (Details) (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	May 01, 2011
Commitments and contingencies
Operating Leases, Future Minimum Payments Due, Next Twelve Months		$ 10
Asset Retirement Obligation, Liabilities Incurred		0	1,000,000
Asset Retirement Obligation, Liabilities Settled		(5,000,000)	(4,000,000)
Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months		1,030,000,000
Environmental
Regulatory assets		1,464,000,000	1,279,000,000
Operating Leases, Rent Expense		14.8	15.8	13.9
Nuclear Generation
Guarantor Obligations, Maximum Exposure, Undiscounted		1,600,000,000
Unrecorded Unconditional Purchase Obligation, Due within Two Years		717,000,000
Unrecorded Unconditional Purchase Obligation, Due within Three Years		530,000,000
Unrecorded Unconditional Purchase Obligation, Due within Four Years		268,000,000
Unrecorded Unconditional Purchase Obligation, Due within Five Years		1,111,000,000
Unrecorded Unconditional Purchase Obligation, Due after Five Years		1,142,000,000
Purchase Obligation		4,798,000,000
Asset Retirement Obligation, Accretion Expense		24,000,000	23,000,000
Asset Retirement Obligation, Revision of Estimate		69,000,000	(44,000,000)
Asset Retirement Obligation		561,000,000	473,000,000	497,000,000
Unrecorded Unconditional Purchase Obligation		1,500,000,000	1,700,000,000	1,900,000,000
Asset Retirement Obligation Other Conditional Obligations		379,000,000
Operating Leases, Future Minimum Payments, Due in Two Years		6
Operating Leases, Future Minimum Payments, Due in Three Years		4
Operating Leases, Future Minimum Payments, Due in Four Years		2
Operating Leases, Future Minimum Payments, Due in Five Years		1
Operating Leases, Future Minimum Payments, Due Thereafter		26
Operating Leases, Future Minimum Payments Due		49
SCE&G
Commitments and contingencies
Operating Leases, Future Minimum Payments Due, Next Twelve Months		6
Asset Retirement Obligation, Liabilities Incurred		0	0
Asset Retirement Obligation, Liabilities Settled		(5,000,000)	(4,000,000)
Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months		952,000,000
Nuclear Insurance
Federal limit on public liability claims from nuclear incident, approximate		12,600,000,000
scg_Maximum Insurance Coverage for each Nuclear Plant by ANI		375,000,000
Maximum liability assessment per reactor for each nuclear incident		117,500,000	78,300,000
Maximum yearly assessment per reactor		17,500,000
Maximum prosepective insurance premium per nuclear incident		40,600,000
Maximum amount of coverage to nuclear facility for property damage and outage costs		2,750,000,000
Maximum amount of coverage for accidental property damage		500,000,000
Environmental
Number of MGP decommissioned sites that contain residues of by-product chemicals		4
Additional costs to be incurred for remediation		22,200,000
Deferred costs, net of costs previously recovered through rates and insurance settlements included in regulatory assets		38,500,000
Regulatory assets		1,377,000,000	1,206,000,000
Operating Leases, Rent Expense		9.6	10.8	9.3
Nuclear Generation
Estimated cash outflow for plant costs and related transmission infrastructure costs of nuclear electric generation site		6,000,000,000
Jointly Owned Utility Plant, Minimum Period for which Escalation Rates are Considered to Determine Estimated Cash Outlays		1
Jointly Owned Utility Plant, Maximum Period for which Escalation Rates are Considered to Determine Estimated Cash Outlays		5
Capital Cost Related to New Federal Healthcare Etc.	1,000,000
Public Utilities, Property, Plant and Equipment Identifiable Capital Costs		278,000,000
Share in Approved Capital Costs		8,000,000			173,900,000
Public Utilities Additional Labor Expenses for Oversight of New Units		132,000,000
Unrecorded Unconditional Purchase Obligation, Due within Two Years		645,000,000
Unrecorded Unconditional Purchase Obligation, Due within Three Years		460,000,000
Unrecorded Unconditional Purchase Obligation, Due within Four Years		227,000,000
Unrecorded Unconditional Purchase Obligation, Due within Five Years		1,076,000,000
Unrecorded Unconditional Purchase Obligation, Due after Five Years		1,033,000,000
Asset Retirement Obligation, Accretion Expense		23,000,000	23,000,000
Asset Retirement Obligation, Revision of Estimate		67,000,000	(47,000,000)
Asset Retirement Obligation		535,000,000	450,000,000	478,000,000
Asset Retirement Obligation Nuclear Decommissioning		182,000,000
Unrecorded Unconditional Purchase Obligation		672,500,000	717,800,000	859,700,000
Asset Retirement Obligation Other Conditional Obligations		353,000,000
Operating Leases, Future Minimum Payments, Due in Two Years		3
Operating Leases, Future Minimum Payments, Due in Three Years		2
Operating Leases, Future Minimum Payments, Due in Four Years		1
Operating Leases, Future Minimum Payments, Due in Five Years		1
Operating Leases, Future Minimum Payments, Due Thereafter		20
Operating Leases, Future Minimum Payments Due		33
PSNC Energy
Environmental
Number of MGP sites that require environmental clean-up		5
Regulatory assets		3,000,000
SCE&G | SCE&G
Nuclear Insurance
Maximum yearly assessment per reactor		$ 11,700,000