CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Revenues:
Electric Regulated Revenue	$ 2,322.0	$ 2,659.0	$ 2,614.0
Regulated Operating Revenue, Gas	934.0	874.0	788.0
Gas-nonregulated	796.0	874.0	825.0
Regulated and Unregulated Operating Revenue	4,052.0	4,407.0	4,227.0
Utilities Operating Expense [Abstract]
Fuel used in electric generation	671.0	594.0	576.0
Purchased power	92.0	80.0	64.0
Utilities Operating Expense, Gas and Petroleum Purchased	1,128.0	1,156.0	1,054.0
Other operation and maintenance	835.0	728.0	741.0
Utilities Operating Expense, Maintenance and Operations, Affiliate	18.4
Utilities Operating Expense, Impairments	1,376.0	1,118.0
Depreciation and amortization	403.0	382.0	371.0
Other taxes	276.0	264.0	254.0
Utilities Operating Expense	4,781.0	4,322.0	3,060.0
Operating Income	(729.0)	85.0	1,167.0
Other Nonoperating Income (Expense)	173.0	47.0	41.0
Other Income (Expense):
Other income	180.0	79.0	64.0
Other expenses	(46.0)	(55.0)	(52.0)
Interest charges, net of allowance for borrowed funds used during construction	(384.0)	(363.0)	(342.0)
Allowance for equity funds used during construction	19.0	23.0	29.0
Total Other Expense	173.0	47.0	41.0
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	(940.0)	(231.0)	866.0
Income Tax Expense (Benefit)	(412.0)	(112.0)	271.0
Income Available to Common Shareholders	$ (528.0)	$ (119.0)	$ 595.0
Earnings Per Share, Basic and Diluted	$ (3.70)	$ (0.83)	$ 4.16
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ (512.0)	$ (120.0)	$ 611.0
Weighted Average Common Shares Outstanding (millions)
Weighted Average Number of Shares Outstanding, Basic	143	143	143
SCE&G
Operating Revenues:
Electric Regulated Revenue	$ 2,322.0	$ 2,659.0	$ 2,614.0
Electric Domestic Regulated Revenues - Affiliate	5.0	5.0	5.0
Regulated Operating Revenue, Gas	434.0	405.0	366.0
Regulated Operating Revenue Gas, Affiliate	1.0	1.0	1.0
Regulated Operating Revenue	2,762.0	3,070.0	2,986.0
Utilities Operating Expense [Abstract]
Fuel used in electric generation	531.0	465.0	472.0
Utilities Operating Expense, Fuel Used, Affiliate	140.0	129.0	104.0
Purchased power	92.0	80.0	64.0
Utilities Operating Expense, Gas and Petroleum Purchased	239.0	206.0	174.0
Utilities Operating Expense, Gas and Petroleum Purchased, affiliate			9.0
Other operation and maintenance	449.0	417.0	403.0
Utilities Operating Expense, Maintenance and Operations, Affiliate	182.0	180.0	199.0
Utilities Operating Expense, Impairments	1,376.0	1,118.0
Depreciation and amortization	327.0	312.0	302.0
Other taxes	251.0	241.0	227.0
Utilities Operating Expense, Taxes, Affiliate	6.0	5.0	7.0
Utilities Operating Expense	3,593.0	3,153.0	1,961.0
Operating Income	(831.0)	(83.0)	1,025.0
Other Nonoperating Income (Expense)	129.0	28.0	19.0
Other Income (Expense):
Other income	141.0	45.0	29.0
Other expenses	(28.0)	(32.0)	(36.0)
Interest charges, net of allowance for borrowed funds used during construction	(303.0)	(288.0)	(270.0)
Allowance for equity funds used during construction	11.0	15.0	26.0
Total Other Expense	129.0	28.0	19.0
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest	(1,005.0)	(343.0)	774.0
Income Tax Expense (Benefit)	(416.0)	(171.0)	248.0
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(589.0)	(172.0)	526.0
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax, Portion Attributable to Parent	1.0	(1.0)	0.0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	(588.0)	(173.0)	526.0
Net Income (Loss) Attributable to Noncontrolling Interest	25.0	13.0	13.0
Earnings Available to Common Shareholder	(613.0)	$ (185.0)	$ 513.0
Subsidiaries [Member] | SCE&G
Other Income (Expense):
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ (589.0)