DERIVATIVE FINANCIAL INSTRUMENTS (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) MMBTU		Dec. 31, 2015 USD ($) MMBTU
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	83,904,223	[1]	58,229,980
Gas Distribution
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	4,510,000		7,530,000
Energy Marketing [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	79,394,223	[1]	50,699,980
Energy Related Derivative [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU	67,447,223	[1]	38,857,480
Energy Related Derivative [Member] | Energy Marketing [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	67,447,223		38,857,480
Commodity Contract [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	16,457,000		19,372,500
Commodity Contract [Member] | Gas Distribution
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	4,510,000		7,530,000
Commodity Contract [Member] | Energy Marketing [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	11,947,000		11,842,500
Basis Swap [Member] | Energy Related Derivative [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU	730,721		1,842,048
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 115.6		$ 120.0
Not Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, Notional Amount	1,285.0		1,235.0
SCE&G | Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, Notional Amount	36.4		36.4
SCE&G | Not Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 1,285.0		$ 1,235.0

[1] (a) Includes amounts related to basis swap contracts totaling 730,721 MMBTU in 2016 and 1,842,048 MMBTU in 2015.