MGE Energy Inc Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Comprehensive Income [Abstract]
Net Income	$ 29,506	$ 26,629	$ 67,858	$ 61,472
Other comprehensive income, net of tax:
Unrealized gain (loss) on available-for-sale securities, net of tax	0	60	0	189
Comprehensive Income	$ 29,506	$ 26,689	$ 67,858	$ 61,661

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

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