ORGANIZATION AND BASIS OF PRESENTATION - Sale of Alabama Gas Corporation (Details) - USD ($) $ in Thousands		12 Months Ended
Sep. 02, 2014	Dec. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Pre-tax gain on disposal of discontinued operations		$ 724,594
Alabama Gas Corporation
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, consideration	$ 1,600,000
Debt assumed	267,000
Proceeds from sale	1,320,000
Pre-tax gain on disposal of discontinued operations	$ 726,500

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Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 45
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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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