RATE AND OTHER REGULATORY MATTERS (Details) (USD $)	9 Months Ended	12 Months Ended	3 Months Ended	9 Months Ended		12 Months Ended						3 Months Ended						9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Dec. 31, 2012 SCEG	Sep. 30, 2013 SCEG	Sep. 30, 2012 SCEG	May 01, 2015 SCEG	Dec. 31, 2012 SCEG	May 15, 2014 SCEG	Oct. 01, 2013 SCEG	Mar. 31, 2013 SCEG	Jun. 30, 2012 SCEG	Mar. 31, 2012 PSNC Energy	Sep. 30, 2013 PSNC Energy	Sep. 30, 2013 Deferred Pollution Control Costs	Dec. 31, 2012 Deferred Pollution Control Costs	Sep. 30, 2013 Deferred Pollution Control Costs SCEG	Dec. 31, 2012 Deferred Pollution Control Costs SCEG	Sep. 30, 2013 Franchise agreement Costs	Dec. 31, 2012 Franchise agreement Costs	Sep. 30, 2013 Franchise agreement Costs SCEG	Dec. 31, 2012 Franchise agreement Costs SCEG
Rate Matters [Line Items]
Regulatory Assets, Noncurrent	$ 1,333,000,000	$ 1,464,000,000	$ 1,377,000,000	$ 1,259,000,000			$ 1,377,000,000						$ 2,900,000	$ 37,000,000	$ 38,000,000	$ 37,000,000	$ 38,000,000	$ 32,000,000	$ 36,000,000	$ 32,000,000	$ 36,000,000
Amounts Recovered Through Electric Rates to offset Turbine Expenses				17,200,000
Share in Approved Capital Costs							8,000,000
Undercollected balance fuel											80,600,000
Number of coal fired units to be retired			6	2			6			6
Public Utilities, Percent Increase (Decrease) in Retail Electric Rates			4.23%		2.90%		2.30%
Allowable return on common equity (as a percent)			10.25%	11.00%
historical average temperature							15
Demand Side Management Program Costs, Noncurrent			19,600,000	16,900,000			19,600,000	10,300,000
Regulatory Asset Recovery Assessments						12
Public Utilities Property Plant and Equipment Identifiable Capital Costs							278,000,000
Capital Cost Related to New Federal Healthcare Etc							1,000,000
Public Utilities Additional Labor Expenses for Oversight of New Units							132,000,000
Increase (decrease) in retail electric rate requested under the BLRA				67.2			0
Public Utilities, Percent Increase (Decrease) in Retail Natural Gas Rates		2.10%
Public Utilities changes in Retail Natural Gas Rates Requested and Approved under RSA		0
Basis for rate calculation				12-month rolling average								12
Regulatory Noncurrent Asset Amortization Period	30			30														20
Public Utilities Base Fuel under Collected Balance Recovery Period	12			12	12
MPG enviromental remediatio	26
Defined Benefit Plan, Deferred Debit Attributable to Share of Regulatory Authority			$ 63,000,000				$ 63,000,000		$ 14,000,000