MGE Energy Inc Consolidated Statements of Common Equity (Unaudited) (USD $) In Thousands, except Share data		Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss)/ Income [Member]
Beginning balance, value at Dec. 31, 2011		$ 550,952	$ 23,114	$ 316,268	$ 211,458	$ 112
Beginning balance, shares at Dec. 31, 2011			23,114,000
Net Income		16,048			16,048
Other comprehensive income (loss)		7				7
Common stock dividends declared	[1]	(8,843)			(8,843)
Common stock issued during period		0
Ending balance, value at Mar. 31, 2012		558,164	23,114	316,268	218,663	119
Ending balance, shares at Mar. 31, 2012			23,114,000
Beginning balance, value at Dec. 31, 2012		579,429	23,114	316,268	239,953	94
Beginning balance, shares at Dec. 31, 2012			23,114,000
Net Income		22,584			22,584
Other comprehensive income (loss)		65				65
Common stock dividends declared	[2]	(9,132)			(9,132)
Common stock issued during period		0
Ending balance, value at Mar. 31, 2013		$ 592,946	$ 23,114	$ 316,268	$ 253,405	$ 159
Ending balance, shares at Mar. 31, 2013			23,114,000

[1] $0.383 per share

[2] $0.395 per share