Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date within one year where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.7-03(a)(16))
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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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-Paragraph 1
-Subparagraph (SX 210.7-03.16(a))
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-Publisher FASB
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LONG-TERM AND SHORT-TERM DEBT (Details) - USD ($)	6 Months Ended
LONG-TERM AND SHORT-TERM DEBT (Details) - USD ($)	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Debt Instrument [Line Items]
Related Party Transaction, Due from (to) Related Party, Current	$ 187,000,000		$ 28,000,000
SCEG
Debt Instrument [Line Items]
Debt Instrument, Face Amount	67,800,000		67,800,000
Related Party Transaction, Due from (to) Related Party, Current	144,000,000		$ 37,000,000
Genco
Debt Instrument [Line Items]
Secured Debt	160,000,000
Interest Expense, Debt	0.0606
PSNC Energy [Member]
Debt Instrument [Line Items]
Interest Expense, Debt	0.0433	$ 0.0418
Senior Notes	$ 100,000,000	$ 150,000,000