Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Operating Revenues:
Electric revenues	$ 121,707	$ 112,164	$ 238,998	$ 222,291
Gas revenue	26,291	40,184	126,253	138,995
Total Operating Revenues	147,998	152,348	365,251	361,286
Operating Expenses:
Fuel for electric generation	13,599	13,880	27,406	27,365
Purchased power	5,845	13,621	21,231	26,164
Cost of gas sold	7,289	21,313	75,136	86,115
Other operations and maintenance	52,049	51,526	102,007	101,520
Depreciation and amortization	25,119	21,287	49,730	42,333
Other general taxes	5,707	5,263	11,317	10,468
Total Operating Expenses	109,608	126,890	286,827	293,965
Operating Income	38,390	25,458	78,424	67,321
Other income, net	4,937	7,696	10,292	14,668
Interest expense, net	(7,760)	(6,463)	(15,247)	(13,034)
Income before income taxes	35,567	26,691	73,469	68,955
Income tax provision	(6,886)	(4,930)	(13,710)	(12,774)
Net Income Including Noncontrolling Interest	28,681	21,761	59,759	56,181
Net Income	$ 28,681	$ 21,761	$ 59,759	$ 56,181
Earnings per share of Common Stock - Basic	$ 0.79	$ 0.6	$ 1.65	$ 1.55
Earnings per share of Common Stock - Diluted	0.79	0.6	1.65	1.55
Dividends per share of common stock	$ 0.408	$ 0.388	$ 0.815	$ 0.775
Weighted Average Shares Outstanding - Basic	36,163	36,163	36,163	36,163
Weighted Average Shares Outstanding - Diluted	36,186	36,174	36,183	36,173
MGE [Member]
Operating Revenues:
Electric revenues	$ 121,707	$ 112,164	$ 238,998	$ 222,291
Gas revenue	26,291	40,184	126,253	138,995
Total Operating Revenues	147,998	152,348	365,251	361,286
Operating Expenses:
Fuel for electric generation	13,599	13,880	27,406	27,365
Purchased power	5,845	13,621	21,231	26,164
Cost of gas sold	7,289	21,313	75,136	86,115
Other operations and maintenance	51,835	51,289	101,404	101,034
Depreciation and amortization	25,119	21,287	49,730	42,333
Other general taxes	5,707	5,263	11,317	10,468
Total Operating Expenses	109,394	126,653	286,224	293,479
Operating Income	38,604	25,695	79,027	67,807
Other income, net	3,254	4,519	6,161	8,037
Interest expense, net	(7,815)	(6,470)	(15,335)	(13,047)
Income before income taxes	34,043	23,744	69,853	62,797
Income tax provision	(6,436)	(4,117)	(12,603)	(11,117)
Net Income Including Noncontrolling Interest	27,607	19,627	57,250	51,680
Less Net Income Attributable to Noncontrolling Interest, net of tax	(5,375)	(5,588)	(10,895)	(10,344)
Net Income	$ 22,232	$ 14,039	$ 46,355	$ 41,336