MGE Energy Inc Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Comprehensive Income [Abstract]
Net Income	$ 27,717	$ 22,584
Other comprehensive income (loss), net of tax:
Unrealized gain (loss) on available-for-sale securities, net of tax	7	65
Comprehensive Income	$ 27,724	$ 22,649