RATE AND OTHER REGULATORY MATTERS (Details) (USD $)	3 Months Ended		12 Months Ended			24 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	May 01, 2015	Dec. 31, 2012	Dec. 31, 2011	May 01, 2015	Jan. 31, 2013	Apr. 30, 2012
Rate Matters [Line Items]
Regulatory Assets, Noncurrent	$ 1,451,000,000	$ 1,464,000,000		$ 1,464,000,000
Allowable return on common equity (as a percent)		11.00%
Public Utilities, Percent Increase (Decrease) in Retail Natural Gas Rates				2.10%	2.10%
Public Utilities changes in Retail Natural Gas Rates Requested and Approved under RSA				0	8.6
Basis for rate calculation		12
Regulatory Noncurrent Asset Amortization Period	30
Public Utilities Base Fuel under Collected Balance Recovery Period	12
SCEG
Rate Matters [Line Items]
Regulatory Assets, Noncurrent	1,365,000,000	1,377,000,000		1,377,000,000
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
Public Utilities, Percent Increase (Decrease) in Retail Electric Rates		4.23%		2.30%	2.40%
Allowable return on common equity (as a percent)		10.25%
historical average temperature				15
Demand Side Management Program Costs, Noncurrent	20,600,000	19,600,000		19,600,000	7,000,000		27,200,000
Regulatory Asset Recovery Assessments			12			24
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				0	0
Basis for rate calculation	12-month rolling average
Regulatory Noncurrent Asset Amortization Period	30
Public Utilities Base Fuel under Collected Balance Recovery Period	12
Defined Benefit Plan, Deferred Debit Attributable to Share of Regulatory Authority		63,000,000		63,000,000
PSNC Energy
Rate Matters [Line Items]
Regulatory Assets, Noncurrent	3,000,000
Deferred Pollution Control Costs
Rate Matters [Line Items]
Regulatory Assets, Noncurrent	38,000,000	38,000,000		38,000,000
Deferred Pollution Control Costs | SCEG
Rate Matters [Line Items]
Regulatory Assets, Noncurrent	38,000,000	38,000,000		38,000,000
Franchise agreement Costs
Rate Matters [Line Items]
Regulatory Assets, Noncurrent	34,000,000	36,000,000		36,000,000
Regulatory Noncurrent Asset Amortization Period	20
Franchise agreement Costs | SCEG
Rate Matters [Line Items]
Regulatory Assets, Noncurrent	$ 34,000,000	$ 36,000,000		$ 36,000,000
Utility Plant [Domain]
Rate Matters [Line Items]
Regulatory Noncurrent Asset Amortization Period				14