RATE AND OTHER REGULATORY MATTERS (Details) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2013
SCEG
Rate Matters [Line Items]
Public Utilities changes in Retail Natural Gas Rates Approved under RSA			$ 9.0
Public Utilities, Percent Increase (Decrease) in Retail Natural Gas Rates			2.34%
Capacity of renewable energy facilities by 2020	84.5		84.5
SCPSC Order, Recovery Of Projected DER Program Costs			$ 16.5
SCPSC Order for Increase of Total Fuel Cost Component of Retail Electric Rates to produce a projected under recovery			61.0
SCPSC Order, Approx Annual pension rider decrease amount			11.9
Carrying costs on deferred income tax assets	$ 4.3	$ 3.5	8.6	$ 6.6
SCPSC Order, Annual DSM Program Rate Rider Recovery Amount			37.0
PSNC Energy
Rate Matters [Line Items]
Pipeline integrity mgmt annual revenue requirement approved by NCUC			$ 1.9
Deferred Income Tax Charges [Member]
Rate Matters [Line Items]
Regulatory Noncurrent Asset Amortization Period			85 years
Asset Retirement Obligation Costs [Member]
Rate Matters [Line Items]
Regulatory Noncurrent Asset Amortization Period			110 years
Environmental Restoration Costs [Member]
Rate Matters [Line Items]
MPG environmental remediation			18
Pension costs, electric [Member] | SCEG
Rate Matters [Line Items]
Regulatory Noncurrent Asset Amortization Period					30 years
Defined Benefit Plan, Deferred Debit Attributable to Share of Regulatory Authority	63.0		$ 63.0
Pension costs, gas [Member] | SCEG
Rate Matters [Line Items]
Regulatory Noncurrent Asset Amortization Period					14 years
Defined Benefit Plan, Deferred Debit Attributable to Share of Regulatory Authority	$ 14.0		$ 14.0
Pension Costs [Member] | SCEG
Rate Matters [Line Items]
Regulatory Noncurrent Asset Amortization Period			11 years