Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating Revenues:
Electric revenues	$ 93,961,000	$ 97,077,000	$ 186,989,000	$ 194,546,000
Gas revenue	23,079,000	25,070,000	79,924,000	95,170,000
Total Operating Revenues	117,040,000	122,147,000	266,913,000	289,716,000
Operating Expenses:
Fuel for electric generation	8,692,000	10,403,000	18,398,000	24,320,000
Purchased power	10,856,000	11,036,000	21,342,000	21,887,000
Cost of gas sold	6,339,000	8,875,000	37,137,000	52,128,000
Other operations and maintenance	46,224,000	48,974,000	90,593,000	95,910,000
Depreciation and amortization	18,434,000	18,091,000	36,601,000	35,230,000
Other general taxes	4,975,000	4,985,000	9,882,000	9,948,000
Total Operating Expenses	95,520,000	102,364,000	213,953,000	239,423,000
Operating Income	21,520,000	19,783,000	52,960,000	50,293,000
Other income, net	6,925,000	5,019,000	12,596,000	9,870,000
Interest expense, net	(5,914,000)	(5,749,000)	(11,975,000)	(11,396,000)
Income before income taxes	22,531,000	19,053,000	53,581,000	48,767,000
Income tax provision	(3,740,000)	(3,505,000)	(8,753,000)	(9,213,000)
Net Income Including Noncontrolling Interest	18,791,000	15,548,000	44,828,000	39,554,000
Net Income	$ 18,791,000	$ 15,548,000	$ 44,828,000	$ 39,554,000
Earnings Per Share of Common Stock (basic and diluted)	$ 0.53	$ 0.45	$ 1.28	$ 1.14
Dividends per share of common stock	$ 0.353	$ 0.338	$ 0.705	$ 0.675
Weighted Average Shares Outstanding (basic and diluted)	35,441	34,668	35,054	34,668
MGE [Member]
Operating Revenues:
Electric revenues	$ 93,961,000	$ 97,077,000	$ 186,989,000	$ 194,546,000
Gas revenue	23,079,000	25,070,000	79,924,000	95,170,000
Total Operating Revenues	117,040,000	122,147,000	266,913,000	289,716,000
Operating Expenses:
Fuel for electric generation	8,692,000	10,403,000	18,398,000	24,320,000
Purchased power	10,856,000	11,036,000	21,342,000	21,887,000
Cost of gas sold	6,339,000	8,875,000	37,137,000	52,128,000
Other operations and maintenance	45,893,000	48,673,000	90,043,000	95,335,000
Depreciation and amortization	18,434,000	18,091,000	36,601,000	35,230,000
Other general taxes	4,975,000	4,985,000	9,882,000	9,948,000
Total Operating Expenses	95,189,000	102,063,000	213,403,000	238,848,000
Operating Income	21,851,000	20,084,000	53,510,000	50,868,000
Other income, net	3,531,000	2,958,000	6,911,000	5,165,000
Interest expense, net	(5,935,000)	(6,133,000)	(12,046,000)	(12,128,000)
Income before income taxes	19,447,000	16,909,000	48,375,000	43,905,000
Income tax provision	(3,046,000)	(2,966,000)	(7,417,000)	(7,892,000)
Net Income Including Noncontrolling Interest	16,401,000	13,943,000	40,958,000	36,013,000
Less Net Income Attributable to Noncontrolling Interest, net of tax	(5,768,000)	(5,621,000)	(11,261,000)	(11,111,000)
Net Income	$ 10,633,000	$ 8,322,000	$ 29,697,000	$ 24,902,000