RATE AND OTHER REGULATORY MATTERS (Details 3) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Regulatory Liabilities [Line Items]
Regulatory Assets, Noncurrent	$ 2,202	$ 1,937
Regulatory Liabilities	864	855
SCEG
Regulatory Liabilities [Line Items]
Regulatory Assets, Noncurrent	2,114	1,857
Regulatory Liabilities	630	635
Asset Retirement Obligation Costs [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities	756	732
Asset Retirement Obligation Costs [Member] | SCEG
Regulatory Liabilities [Line Items]
Regulatory Liabilities	533	519
Deferred gains on interest rate derivatives [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities	80	96
Deferred gains on interest rate derivatives [Member] | SCEG
Regulatory Liabilities [Line Items]
Regulatory Liabilities	$ 80	$ 96