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

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MGE Energy Inc Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Other Comprehensive Income [Abstract]
Net Income	$ 16,361	$ 29,506	$ 18,351	$ 20,001	$ 36,134	$ 26,629	$ 15,543	$ 19,300	$ 84,219	$ 97,606	$ 75,560
Other comprehensive income, net of tax:
Unrealized gain (loss) on available for sale securities, net of tax									0	175	(155)
Comprehensive Income									$ 84,219	$ 97,781	$ 75,405