RATE AND OTHER REGULATORY MATTERS RATE AND OTHER REGULATORY MATTERS (Details) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2014 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) $ / shares	Dec. 31, 2014 USD ($)	Dec. 31, 2013
SCE&G
Fuel Cost Increase To Base Fuel Costs		$ 10.3
Deferred Amounts Applied To Undercollected Fuel Balance		46.0
Demand Side Management Program Costs, Noncurrent		$ 37.6	$ 32.0	$ 15.4
Capacity of renewable energy facilities by 2020		84.5
Depreciation Study 2015, Effect Of Lower Depreciation Rates Annually, Dollars			$ 29.0
Depreciation Study 2015, Effect Of Lower Depreciation Rates Annually, Per Share | $ / shares			$ 0.12
Depreciation Study 2015, Undercollected Fuel Amount Offset by Lower Depreciation Rates, Dollars			$ 14.5
Depreciation Study 2015, Undercollected Fuel Amount Offset by Lower Depreciation Rates, Per Share | $ / shares			$ 0.06
Depreciation Study 2015, Increase in Net Income			$ 9.8
SCPSC Order Reduction Of Total Fuel Cost Component Of Retail Electric Rates To Reflect Lower Projected Fuel Costs And Eliminate Over-Collection Balances		$ 61.0
SCPSC Order, Recovery Of Projected DER Program Costs		6.9
Carrying costs on deferred income tax assets		14.0	$ 9.5
Storm Damage Reserve Cost Applied				5.0
Derivative, Gain on Derivative				$ 17.8
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	$ 5.0
DSM Program SCPC January 2017 filing, cost and net lost revenue recovery [Line Items]		$ 37.0
Pipeline integrity management costs [Member] | PSNC Energy [Member]
Regulatory Asset, Amortization Period		5 years
Demand Side Management programs [Member] | SCE&G
Regulatory Asset, Amortization Period		5 years
Deferred Income Tax Charge [Member]
Regulatory Asset, Amortization Period		85 years
Pension Costs [Member] | SCE&G
Regulatory Asset, Amortization Period		11 years
Pension costs, electric [Member] | SCE&G
Regulatory Asset, Amortization Period					30 years
Pension costs, gas [Member] | SCE&G
Regulatory Asset, Amortization Period					14 years
Asset Retirement Obligation Costs [Member]
Regulatory Asset, Amortization Period		110 years