v3.10.0.1

REVENUE RECOGNITION (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Contract with Customer, Liability	$ 9.4				$ 8.3				$ 9.4	$ 8.3
Total Operating Revenues Gas									931.0
Regulated Operating Revenue, Gas									934.0	874.0	$ 788.0
Electric Regulated Revenue									2,322.0	2,659.0	2,614.0
Residential [Member]
Gas -non regulated revenues									244.0
Total Operating Revenues Gas									533.0
Commercial [Member]
Gas -non regulated revenues									92.0
Total Operating Revenues Gas									242.0
Industrial [Member]
Gas -non regulated revenues									422.0
Total Operating Revenues Gas									107.0
Wholesale [Member]
Gas -non regulated revenues									38.0
Total Operating Revenues Gas									4.0
Gas Distribution
Regulated Operating Revenue, Other									4.0
Total Operating Revenues Gas									935.0
Gas Marketing segment [Member]
Regulated Operating Revenue, Other									0.0
Regulated Operating Revenue									796.0
Revenue from Contract with Customer, Excluding Assessed Tax									796.0
SCE&G
Contract with Customer, Liability	3.6				2.9				3.6	2.9
Regulated Operating Revenue	689.0	$ 739.0	$ 632.0	$ 702.0	739.0	$ 856.0	$ 756.0	$ 719.0	2,762.0	3,070.0	2,986.0
Capitalized Contract Cost, Amortization									(1.5)
Capitalized Contract Cost, Gross	0.0								0.0
Capitalized Contract Cost, Net	$ 14.8				$ 16.3				14.8	16.3
Regulated Operating Revenue, Gas									434.0	405.0	366.0
Electric Regulated Revenue									2,322.0	$ 2,659.0	$ 2,614.0
SCE&G | Residential [Member]
Regulated Operating Revenue, Gas									208.0
Electric Regulated Revenue									1,054.0
SCE&G | Commercial [Member]
Regulated Operating Revenue, Gas									117.0
Electric Regulated Revenue									744.0
SCE&G | Industrial [Member]
Regulated Operating Revenue, Gas									92.0
Electric Regulated Revenue									385.0
SCE&G | Transportation [Member] [Domain]
Gas -non regulated revenues									0.0
Total Operating Revenues Gas									45.0
Regulated Operating Revenue, Gas									13.0
Electric Regulated Revenue									0.0
SCE&G | Wholesale [Member]
Regulated Operating Revenue, Gas									4.0
Electric Regulated Revenue									132.0
SCE&G | Electric Operations
Regulated Operating Revenue, Other									12.0
Regulated Operating Revenue									2,327.0
Revenue from Contract with Customer, Excluding Assessed Tax									2,315.0
SCE&G | Gas Distribution
Regulated Operating Revenue, Other									1.0
Regulated Operating Revenue									435.0
Revenue from Contract with Customer, Excluding Assessed Tax									434.0
PSNC Energy [Member] | Residential [Member]
Regulated Operating Revenue, Gas									325.0
PSNC Energy [Member] | Commercial [Member]
Regulated Operating Revenue, Gas									125.0
PSNC Energy [Member] | Industrial [Member]
Regulated Operating Revenue, Gas									15.0
PSNC Energy [Member] | Transportation [Member] [Domain]
Regulated Operating Revenue, Gas									32.0
PSNC Energy [Member] | Wholesale [Member]
Regulated Operating Revenue, Gas									0.0
PSNC Energy [Member] | Gas Distribution
Regulated Operating Revenue, Other									3.0
Regulated Operating Revenue									500.0
Revenue from Contract with Customer, Excluding Assessed Tax									$ 497.0

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