FAIR VALUE (Details 2) (USD $) In Millions, unless otherwise specified							12 Months Ended			12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Fair value measurements on a recurring basis Level 3	Dec. 31, 2012 Fair value measurements on a recurring basis Level 3	Dec. 31, 2013 Fair value measurements on a recurring basis Level 3 FTRs	Dec. 31, 2012 Fair value measurements on a recurring basis Level 3 FTRs	Dec. 31, 2013 Fair value measurements on a recurring basis Level 3 FTRs Valuation Technique: Market-based Average	Dec. 31, 2013 Fair value measurements on a recurring basis Level 3 Coal contract	Dec. 31, 2012 Fair value measurements on a recurring basis Level 3 Coal contract	Dec. 31, 2013 Fair value measurements on a recurring basis Level 3 Coal contract Valuation Technique: Market-based Minimum	Dec. 31, 2013 Fair value measurements on a recurring basis Level 3 Coal contract Valuation Technique: Market-based Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information
Risk Management Asset	$ 2.4	$ 3.9	$ 1.7	$ 3.7	$ 1.5	$ 1.2		$ 0.2	$ 2.5
Risk Management Liability	$ 3.1	$ 9.7	$ 3.0	$ 9.1	$ 0.3	$ 0.1		$ 2.7	$ 9.0
Fair Value Inputs
Forward market prices (in dollars per megawatt-month or ton)							121.68			11.73	14.30