EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS (Details 5) - USD ($) $ in Millions	4 Months Ended	8 Months Ended	12 Months Ended
	Dec. 31, 2013	Aug. 31, 2013	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax				$ 0.0	$ 1.0	$ 1.0
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax				$ 0.0	4.0	(8.0)
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate				5.00%
Defined Contribution Plan, Maximum Percentage of Employer Contribution for up to Six Percent of Participant Contribution				100.00%
Defined Contribution Plan, Maximum Percentage of Participant Contribution Eligible for Employer Contribution Match				6.00%
Defined Contribution Plan, Cost Recognized				$ 26.2	25.8	$ 23.4
Pension Plan, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Pension Plan, Liabilities, Noncurrent				$ 73.7	$ 57.7
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	5.07%	4.10%		4.20%	5.03%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets				7.50%	8.00%	8.00%
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax				$ 2.7	$ 3.1	$ (5.0)
Amortization of deferred employee benefit plan costs reclassified to net income, net of tax				(0.4)	(0.2)	(0.5)
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Net of Tax				(0.1)	(0.2)	(0.2)
Other Comprehensive Income, Other Adjustments to Defined Benefit Plan, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Net of Tax				0.0	0.0	(0.3)
Defined Benefit Plan, Amortization of Net Transition Asset (Obligation)				0.0	0.0	0.0
Defined Benefit Plan, Service Cost				24.1	20.0	21.8
Defined Benefit Plan, Interest Cost				38.2	40.4	38.5
Defined Benefit Plan, Expected Return on Plan Assets				(62.0)	(66.7)	(61.4)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)				4.1	4.1	6.0
Defined Benefit Plan, Amortization of Gains (Losses)				13.6	4.8	16.9
Defined Benefit Plan, Amortization of Transition Obligations (Assets)				0.0	0.0	0.0
Defined Benefit Plan, Curtailments				0.0	0.0	9.9
Defined Benefit Plan, Net Periodic Benefit Cost				18.0	2.6	31.7
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax				$ 2.2	$ 2.7	$ (6.0)
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase	3.00%	3.75%		3.00%	3.00%
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate				4.30%	5.19%	4.19%
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax				$ (1.2)	$ 1.3	$ (1.8)
Amortization of deferred employee benefit plan costs reclassified to net income, net of tax				(0.1)	0.0	(0.2)
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Net of Tax				(0.1)	0.0	0.0
Other Comprehensive Income, Other Adjustments to Defined Benefit Plan, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Net of Tax				0.0	0.0	0.0
Defined Benefit Plan, Amortization of Net Transition Asset (Obligation)				0.0	0.0	(0.1)
Defined Benefit Plan, Service Cost				5.3	4.6	5.9
Defined Benefit Plan, Interest Cost				11.4	12.0	11.1
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)				0.4	0.3	0.7
Defined Benefit Plan, Amortization of Gains (Losses)				2.1	0.0	3.3
Defined Benefit Plan, Amortization of Transition Obligations (Assets)				0.0	0.0	0.3
Defined Benefit Plan, Net Periodic Benefit Cost				19.2	16.9	21.3
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax				$ (1.4)	$ 1.3	$ (2.1)
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase				3.00%	3.75%	3.75%
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year				7.00%	7.40%	7.80%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate				5.00%	5.00%	5.00%
SCE&G
Defined Benefit Plan Disclosure [Line Items]
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax				$ 0.0	$ 0.0	$ 1.0
Amortization of deferred employee benefit plan costs reclassified to net income, net of tax				$ 0.0	0.0	0.0
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate				5.00%
Defined Contribution Plan, Maximum Percentage of Employer Contribution for up to Six Percent of Participant Contribution				100.00%
Defined Contribution Plan, Maximum Percentage of Participant Contribution Eligible for Employer Contribution Match				6.00%
Defined Contribution Plan, Cost Recognized				$ 21.8	20.7	$ 18.7
SCE&G | Pension Plan, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Pension Plan, Liabilities, Noncurrent					$ 0.0
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	5.07%	4.10%		4.20%	5.03%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets				7.50%	8.00%	8.00%
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax				$ 0.2	$ 0.2	$ (0.8)
Amortization of deferred employee benefit plan costs reclassified to net income, net of tax				(0.1)	(0.1)	(0.1)
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Net of Tax				(0.1)	(0.1)	0.0
Defined Benefit Plan, Service Cost				19.3	16.0	17.6
Defined Benefit Plan, Interest Cost				32.2	34.1	32.6
Defined Benefit Plan, Expected Return on Plan Assets				(52.2)	(56.3)	(51.9)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)				3.4	3.5	5.0
Defined Benefit Plan, Amortization of Gains (Losses)				11.4	4.0	14.3
Defined Benefit Plan, Curtailments				0.0	0.0	8.4
Defined Benefit Plan, Net Periodic Benefit Cost				14.1	1.3	26.0
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax				$ 0.0	$ 0.0	$ (0.9)
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase	3.00%	3.75%		3.00%	3.00%
SCE&G | Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate				4.30%	5.19%	4.19%
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax				$ (0.3)	$ 0.4	$ (0.4)
Amortization of deferred employee benefit plan costs reclassified to net income, net of tax				0.0	0.0	(0.1)
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Net of Tax				0.0	0.0	0.0
Defined Benefit Plan, Service Cost				4.4	3.6	4.6
Defined Benefit Plan, Interest Cost				9.4	9.4	8.7
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)				0.3	0.3	0.6
Defined Benefit Plan, Amortization of Gains (Losses)				1.7	0.0	2.6
Defined Benefit Plan, Net Periodic Benefit Cost				15.8	13.3	16.5
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax				$ (0.3)	$ 0.4	$ (0.5)
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase				3.00%	3.75%	3.75%
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year				7.00%	7.40%	7.80%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate				5.00%	5.00%	5.00%
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets			7.50%
Scenario, Forecast [Member] | Pension Plan, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Net Gains (Losses)			$ 0.6
Defined Benefit Plan, Amortization of Net Prior Service Cost (Credit)			0.2
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year			0.8
Scenario, Forecast [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Net Gains (Losses)			0.0
Defined Benefit Plan, Amortization of Net Prior Service Cost (Credit)			0.0
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year			$ 0.0
Scenario, Forecast [Member] | SCE&G
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets			7.50%