Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating Revenues:
Electric revenues	$ 465,847	$ 420,964	$ 394,372
Gas revenue	248,672	185,620	144,261
Total Operating Revenues	714,519	606,584	538,633
Operating Expenses:
Fuel for electric generation	61,329	54,633	41,684
Purchased power	46,821	39,395	42,883
Cost of gas sold	152,570	99,690	63,697
Other operations and maintenance	209,875	199,316	186,430
Depreciation and amortization	85,549	76,983	74,188
Other general taxes	20,632	19,273	19,754
Total Operating Expenses	576,776	489,290	428,636
Operating Income	137,743	117,294	109,997
Other income, net	26,080	16,694	25,365
Interest (expense) income, net	(26,647)	(24,112)	(23,521)
Income before income taxes	137,176	109,876	111,841
Income tax provision	(26,224)	(4,115)	(19,423)
Net Income Including Noncontrolling Interest	110,952	105,761	92,418
Net Income	$ 110,952	$ 105,761	$ 92,418
Earnings Per Share of Common Stock, Basic	$ 3.07	$ 2.92	$ 2.60
Earnings Per Share of Common Stock, Diluted	3.07	2.92	2.60
Dividends per share of common stock	$ 1.59	$ 1.52	$ 1.45
Weighted Average Shares Outstanding, Basic	36,163	36,163	35,612
Weighted Average Shares Outstanding, Diluted	36,174	36,167	35,612
MGE [Member]
Operating Revenues:
Electric revenues	$ 465,847	$ 420,964	$ 394,372
Gas revenue	248,672	185,620	144,261
Total Operating Revenues	714,519	606,584	538,633
Operating Expenses:
Fuel for electric generation	61,329	54,633	41,684
Purchased power	46,821	39,395	42,883
Cost of gas sold	152,570	99,690	63,697
Other operations and maintenance	209,007	198,552	185,450
Depreciation and amortization	85,549	76,983	74,188
Other general taxes	20,627	19,269	19,750
Total Operating Expenses	575,903	488,522	427,652
Operating Income	138,616	118,062	110,981
Other income, net	17,626	9,121	15,019
Interest (expense) income, net	(26,687)	(24,153)	(23,642)
Income before income taxes	129,555	103,030	102,358
Income tax provision	(24,063)	(2,248)	(16,835)
Net Income Including Noncontrolling Interest	105,492	100,782	85,523
Less Net Income Attributable to Noncontrolling Interest, net of tax	(21,576)	(22,391)	(22,393)
Net Income	$ 83,916	$ 78,391	$ 63,130