SCHEDULE II (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	$ 7	$ 6	$ 6	$ 5
Valuation Allowances and Reserves, Charged to Cost and Expense	15	13	12
Valuation Allowances and Reserves, Charged to Other Accounts	0	0	0
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction	14	13	11
General Liability [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	7	9	9	6
Valuation Allowances and Reserves, Charged to Cost and Expense	5	8	5
Valuation Allowances and Reserves, Charged to Other Accounts	0	0	0
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction	7	8	2
SCE&G \| SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	4	4	3	3
Valuation Allowances and Reserves, Charged to Cost and Expense	7	8	6
Valuation Allowances and Reserves, Charged to Other Accounts	0	0	0
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction	7	7	6
SCE&G \| General Liability [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	6	8	8	$ 5
Valuation Allowances and Reserves, Charged to Cost and Expense	5	8	5
Valuation Allowances and Reserves, Charged to Other Accounts	0	0	0
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction	$ 7	$ 8	$ 2

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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