DERIVATIVE FINANCIAL INSTRUMENTS OFFSETTING ASSETS AND LIABILITIES (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Derivative Liability	$ 64	$ 106
Derivative Asset, Fair Value, Gross Liability	(4)	(1)
Derivative Assets, Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments	(9)	(8)
Derivative, Collateral, Obligation to Return Cash
Derivative Asset, Fair Value, Gross Asset	90	31
Derivative Liability, Fair Value, Gross Asset	(3)	(1)
Derivative Liabilities, Net Amount	26	48
Derivative Liability, Fair Value, Gross Liability	67	107
Derivative Liabilities, Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments	(9)	(8)
Derivative Liabilities, Gross Amounts Not Offset in the Statement of Financial Position - Cash Collateral Posted	(29)	(50)
Derivative Assets, Net Amount	77	22
Derivative Asset	86	30
Other Deferred Debits and Other Assets [Member]
Derivative [Line Items]
Derivative Asset	72	8
Other Current Assets [Member]
Derivative [Line Items]
Derivative Liability		3
Derivative Asset	5	22
Other Current Liabilities [Member]
Derivative [Line Items]
Derivative Liability	35	50
Other Deferred Credits and Other Liabilities
Derivative [Line Items]
Derivative Liability	29	53
Prepayments [Member]
Derivative [Line Items]
Derivative Asset	9
SCE&G
Derivative [Line Items]
Derivative Liability	39	65
Derivative Asset	71	15
SCE&G | Other Deferred Debits and Other Assets [Member]
Derivative [Line Items]
Derivative Asset	71	5
SCE&G | Other Current Assets [Member]
Derivative [Line Items]
Derivative Asset		10
SCE&G | Other Current Liabilities [Member]
Derivative [Line Items]
Derivative Liability	28	34
SCE&G | Other Deferred Credits and Other Liabilities
Derivative [Line Items]
Derivative Liability	11	31
Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Liability	58	87
Derivative Assets, Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments	(9)	(8)
Derivative Asset, Fair Value, Gross Asset	71	15
Derivative Liabilities, Net Amount	20	43
Derivative Liability, Fair Value, Gross Liability	58	87
Derivative Liabilities, Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments	(9)	(8)
Derivative Liabilities, Gross Amounts Not Offset in the Statement of Financial Position - Cash Collateral Posted	(29)	(36)
Derivative Assets, Net Amount	62	7
Derivative Asset	71	15
Interest Rate Contract [Member] | SCE&G
Derivative [Line Items]
Derivative Liability	39	65
Derivative Assets, Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments	(9)	(8)
Derivative Asset, Fair Value, Gross Asset	71	15
Derivative Liabilities, Net Amount	21	44
Derivative Liability, Fair Value, Gross Liability	39	65
Derivative Liabilities, Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments	(9)	(8)
Derivative Liabilities, Gross Amounts Not Offset in the Statement of Financial Position - Cash Collateral Posted	(9)	(13)
Derivative Assets, Net Amount	62	7
Derivative Asset	71	15
Commodity Contract [Member]
Derivative [Line Items]
Derivative Liability	0	5
Derivative Asset, Fair Value, Gross Asset	9	1
Derivative Liabilities, Net Amount	0	0
Derivative Liability, Fair Value, Gross Liability		5
Derivative Liabilities, Gross Amounts Not Offset in the Statement of Financial Position - Cash Collateral Posted		(5)
Derivative Assets, Net Amount	9	1
Derivative Asset	9	1
Other Energy Management Contract [Member]
Derivative [Line Items]
Derivative Liability	6	14
Derivative Asset, Fair Value, Gross Liability	(4)	(1)
Derivative Asset, Fair Value, Gross Asset	10	15
Derivative Liability, Fair Value, Gross Asset	(3)	(1)
Derivative Liabilities, Net Amount	6	5
Derivative Liability, Fair Value, Gross Liability	9	15
Derivative Liabilities, Gross Amounts Not Offset in the Statement of Financial Position - Cash Collateral Posted		(9)
Derivative Assets, Net Amount	6	14
Derivative Asset	$ 6	$ 14