Cost of natural gas purchased and associated transportation and storage costs during the period.

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- Definition

Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due within 1 year (or 1 business cycle).

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- Definition

Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of transactions with related party during the financial reporting period.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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No definition available.

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AFFILIATED TRANSACTIONS -SCEG (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Sep. 30, 2014
Canadys Refined Coal [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction	$ 69.7	$ 39.0
Due to Affiliate, Current	18.6		27.9
Due from Affiliate, Current	18.5		27.8
Equity Method Investment, Ownership Percentage	40.00%
CGT [Member]
Related Party Transaction [Line Items]
Related Party Transaction Purchases from Related Party	3.4	5.5
Due to Affiliate, Current			3.3
Due from Affiliate, Current			1.2	0
Energy Marketing [Member]
Related Party Transaction [Line Items]
Due to Affiliate, Current	10.6		12.6
Cost of Natural Gas Purchases	34.6	53.4
Canadys Refined Coal [Member]
Related Party Transaction [Line Items]
Related Party Transaction Purchases from Related Party	70.1	39.2
SCANA Services [Member]
Related Party Transaction [Line Items]
Related Party Transaction Purchases from Related Party	48.4		47.3
Related Party Transaction, Expenses from Transactions with Related Party	$ 73.1	$ 76.2