Related Party Transactions	12 Months Ended
Dec. 31, 2013
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions - MGE Energy and MGE. ATC During 2013, 2012, and 2011, MGE recorded $27.7 million, $25.3 million, and $25.0 million, respectively, for transmission services received from ATC. MGE also provides a variety of operational, maintenance, and project management work for ATC, which is reimbursed by ATC. For the years ended December 31, 2013, 2012, and 2011, MGE had a receivable due from ATC of $0.2 million. For additional discussion on MGE's relationship with ATC, see Footnote 4.

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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