COMMON EQUITY (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Schedule of Capitalization, Equity [Line Items]
Common Stock, Shares Authorized	200.0		200.0		200.0
COMMON EQUITY [Abstract]
Common Stock, Shares, Outstanding	142.9		142.9		142.9
SCEG
Schedule of Capitalization, Equity [Line Items]
Common Stock, Shares Authorized	50.0		50.0		50.0
COMMON EQUITY [Abstract]
Common Stock, Shares, Outstanding	40.3		40.3		40.3
Preferred Stock, Shares Authorized	20.0		20.0		20.0
Preferred Stock, Shares Outstanding	0.0		0.0		0.0
Commodity Contract
Schedule of Capitalization, Equity [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ 0	$ (1)	$ (6)	$ (10)
Interest Rate Contract [Member]
Schedule of Capitalization, Equity [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(2)	(2)	(6)	(6)
Gas Purchased for Resale [Member] [Member] | Cash Flow Hedging [Member] | Commodity Contract
Schedule of Capitalization, Equity [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	0	1	6	10
Interest Expense [Member] | Cash Flow Hedging [Member] | Interest Rate Contract [Member]
Schedule of Capitalization, Equity [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ 2	$ 2	$ 6	$ 6