MGE Energy Inc Consolidated Statements of Common Equity (Unaudited) (USD $) In Thousands		Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive 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
Net Income		53,960			53,960
Other comprehensive income (loss)		35				35
Common stock dividends declared	[1]	(26,820)			(26,820)
Ending balance, value at Sep. 30, 2012		578,127	23,114	316,268	238,598	147
Ending balance, shares at Sep. 30, 2012			23,114
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
Net Income		60,828			60,828
Other comprehensive income (loss)		176				176
Common stock dividends declared	[2]	(27,685)			(27,685)
Ending balance, value at Sep. 30, 2013		$ 612,748	$ 23,114	$ 316,268	$ 273,096	$ 270
Ending balance, shares at Sep. 30, 2013			23,114

[1] $1.161 per share

[2] $1.198 per share