MGE Energy Inc Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Comprehensive Income [Abstract]
Net Income	$ 20,001	$ 19,300
Other comprehensive income, net of tax:
Unrealized gain (loss) on available-for-sale securities, net of tax	0	97
Comprehensive Income	$ 20,001	$ 19,397

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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-Section 45
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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