Investment in ATC (Details-1) (USD $)	3 Months Ended		0 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 MGE Transco [Member] ATC [Member]	Mar. 31, 2013 MGE Transco [Member] ATC [Member]	Dec. 31, 2013 MGE Transco [Member] ATC [Member]	Apr. 30, 2014 MGE Transco [Member] ATC [Member] Subsequent Event [Member]
Schedule Of Equity Method Investments [Line Items]
Equity earnings from investment	$ 2,481,000	$ 2,396,000	$ 2,481,000	$ 2,396,000
Dividend income from investment	1,917,000	1,807,000	1,917,000	1,807,000
Capital contributions to investment	693,000	373,000	533,000	178,000		500,000
Equity method investment			$ 65,600,000		$ 64,500,000

This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

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+ References

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+ References

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