MGE Energy Inc Consolidated Statements of Income (Unaudited) (MGE Energy [Member], USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
MGE Energy [Member]
Operating Revenues:
Regulated electric revenues	$ 90,834	$ 87,438	$ 176,841	$ 169,432
Regulated gas revenues	25,062	20,290	102,499	96,837
Nonregulated revenues	1,363	1,354	2,524	2,456
Total Operating Revenues	117,259	109,082	281,864	268,725
Operating Expenses:
Fuel for electric generation	11,599	10,242	22,648	19,143
Purchased power	14,392	16,467	31,973	37,934
Cost of gas sold	13,052	9,792	63,999	62,476
Other operations and maintenance	40,657	38,693	80,070	79,723
Depreciation and amortization	10,357	9,481	20,373	18,703
Other general taxes	4,005	4,285	8,706	8,849
Total Operating Expenses	94,062	88,960	227,769	226,828
Operating Income	23,197	20,122	54,095	41,897
Other income, net	2,153	1,947	4,539	6,668
Interest expense, net	(5,055)	(4,045)	(9,905)	(7,953)
Income before income taxes	20,295	18,024	48,729	40,612
Income tax provision	(7,572)	(6,472)	(18,223)	(14,800)
Net Income	$ 12,723	$ 11,552	$ 30,506	$ 25,812
Earnings Per Share of Common Stock (basic and diluted)	$ 0.55	$ 0.50	$ 1.32	$ 1.12
Dividends per share of common stock	$ 0.375	$ 0.368	$ 0.750	$ 0.737
Average Shares Outstanding (basic and diluted)	23,114	23,114	23,114	23,114