RISK MANAGEMENT AND DERIVATIVE FINANCIAL INSTRUMENTS (Details 3)	12 Months Ended
Dec. 31, 2015 USD ($) item MWh $ / item
Transmission congestion rights (TCR) - 2015
Procurement guidelines
Monthly MWH Hedged \| MWh	3,212.00
Monthly MWH Hedged, estimated fair value \| $	$ 1,292,943
Electric \| Natural Gas Usage - 2016
Volumes and percentage of anticipated volume of natural gas usage
% Hedged	61.00%
Dth Hedged Physical	2,706,000
Dth Hedged Financial	5,940,000
Average Price (in dollars per dth) \| $ / item	3.372
Electric \| Natural Gas Usage - 2017
Volumes and percentage of anticipated volume of natural gas usage
% Hedged	41.00%
Dth Hedged Physical	782,900
Dth Hedged Financial	5,210,000
Average Price (in dollars per dth) \| $ / item	3.347
Electric \| Natural Gas Usage - 2018
Volumes and percentage of anticipated volume of natural gas usage
% Hedged	20.00%
Dth Hedged Physical	565,000
Dth Hedged Financial	2,460,000
Average Price (in dollars per dth) \| $ / item	3.334
Electric \| Natural Gas Forward 2019
Volumes and percentage of anticipated volume of natural gas usage
% Hedged	10.00%
Dth Hedged Financial	1,460,000
Average Price (in dollars per dth) \| $ / item	2.955
Electric \| Natural Gas Forward 2020
Volumes and percentage of anticipated volume of natural gas usage
% Hedged	0.00%
Electric \| Current Year Procurement Guidelines
Procurement guidelines
Maximum percentage of volume to be hedged in any given month	100.00%
Maximum flexibility to hedge any future year's expected requirements (as a percent)	80.00%
Electric \| First Year Procurement Guidelines
Volumes and percentage of anticipated volume of natural gas usage
% Hedged	60.00%
Electric \| Second Year Procurement Guidelines
Volumes and percentage of anticipated volume of natural gas usage
% Hedged	40.00%
Electric \| Third Year Procurement Guidelines
Volumes and percentage of anticipated volume of natural gas usage
% Hedged	20.00%
Electric \| Fourth Year Procurement Guidelines
Volumes and percentage of anticipated volume of natural gas usage
% Hedged	10.00%
Electric \| High end of range \| Current Year Procurement Guidelines
Volumes and percentage of anticipated volume of natural gas usage
% Hedged	100.00%

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Represents the maximum flexibility to hedge any future year's expected requirements.

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Nominal volume used to calculate payments on a derivative instrument.

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The notional amount of financial derivatives expressed in nonmonetary units.

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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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The average forward price on the group of price risk forward or futures contracts, such as gas futures contracts.

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The percentage of expected requirements covered by the aggregate notional amount of derivative contracts expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract as a percentage of expected need.

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