RISK MANAGEMENT AND DERIVATIVE FINANCIAL INSTRUMENTS (Details 2) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Electric
Gain / (Loss) on derivatives
Unrealized net losses applicable to financial instruments which will settle in next twelve months	$ 6,000,000
Period within which financial instruments will settle	12 months
Amount of Gain/(Loss) Recognized on Balance Sheet	6,178,000	1,629,000
Amount of Gain / (Loss) Recognized in Income on Derivative	9,447,000	(2,644,000)
Gas
Gain / (Loss) on derivatives
Amount of Gain/(Loss) Recognized on Balance Sheet	(511,000)	(5,000)
Commodity contracts \| Electric
Gain / (Loss) on derivatives
Amount of Gain/(Loss) Recognized on Balance Sheet	(6,780,000)	(338,000)
Amount of Gain / (Loss) Recognized in Income on Derivative	(1,659,000)	(2,725,000)
Commodity contracts \| Gas
Gain / (Loss) on derivatives
Amount of Gain/(Loss) Recognized on Balance Sheet	(511,000)	(5,000)
Transmission congestion rights (TCR) \| Electric
Gain / (Loss) on derivatives
Amount of Gain/(Loss) Recognized on Balance Sheet	12,958,000	1,967,000
Amount of Gain / (Loss) Recognized in Income on Derivative	$ 11,106,000	$ 81,000

Represents the net gain (loss) from the increase (decrease) in the fair value of derivative instrument not designated as hedging instrument, recognized on the balance sheet as regulatory (assets)/liabilities.

No definition available.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

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- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The estimated net amount of unrealized gains or losses on price risk cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7668309&loc=d3e80748-113994

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