Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Operating Revenues:
Electric revenues	$ 139,104	$ 133,090	$ 378,102	$ 355,381
Gas revenue	21,424	30,310	147,677	169,305
Total Operating Revenues	160,528	163,400	525,779	524,686
Operating Expenses:
Fuel for electric generation	19,712	21,045	47,118	48,410
Purchased power	7,021	9,593	28,252	35,757
Cost of gas sold	5,160	14,523	80,296	100,638
Other operations and maintenance	53,997	49,194	156,004	150,714
Depreciation and amortization	25,241	21,447	74,971	63,780
Other general taxes	5,605	5,111	16,922	15,579
Total Operating Expenses	116,736	120,913	403,563	414,878
Operating Income	43,792	42,487	122,216	109,808
Other income, net	10,549	6,068	20,841	20,736
Interest expense, net	(7,654)	(6,652)	(22,901)	(19,686)
Income before income taxes	46,687	41,903	120,156	110,858
Income tax provision	(8,830)	(8,183)	(22,540)	(20,957)
Net Income Including Noncontrolling Interest	37,857	33,720	97,616	89,901
Net Income	$ 37,857	$ 33,720	$ 97,616	$ 89,901
Earnings per share of Common Stock - Basic	$ 1.05	$ 0.93	$ 2.7	$ 2.49
Earnings per share of Common Stock - Diluted	1.05	0.93	2.7	2.49
Dividends per share of common stock	$ 0.428	$ 0.408	$ 1.243	$ 1.183
Weighted Average Shares Outstanding - Basic	36,163	36,163	36,163	36,163
Weighted Average Shares Outstanding - Diluted	36,189	36,176	36,185	36,174
MGE [Member]
Operating Revenues:
Electric revenues	$ 139,104	$ 133,090	$ 378,102	$ 355,381
Gas revenue	21,424	30,310	147,677	169,305
Total Operating Revenues	160,528	163,400	525,779	524,686
Operating Expenses:
Fuel for electric generation	19,712	21,045	47,118	48,410
Purchased power	7,021	9,593	28,252	35,757
Cost of gas sold	5,160	14,523	80,296	100,638
Other operations and maintenance	53,847	48,989	155,251	150,024
Depreciation and amortization	25,241	21,447	74,971	63,780
Other general taxes	5,605	5,106	16,922	15,573
Total Operating Expenses	116,586	120,703	402,810	414,182
Operating Income	43,942	42,697	122,969	110,504
Other income, net	7,824	4,430	13,985	12,467
Interest expense, net	(7,721)	(6,662)	(23,056)	(19,709)
Income before income taxes	44,045	40,465	113,898	103,262
Income tax provision	(8,093)	(7,664)	(20,696)	(18,781)
Net Income Including Noncontrolling Interest	35,952	32,801	93,202	84,481
Less Net Income Attributable to Noncontrolling Interest, net of tax	(5,487)	(5,603)	(16,382)	(15,947)
Net Income	$ 30,465	$ 27,198	$ 76,820	$ 68,534