Summary of Significant Accounting Policies (Details-2) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Supplemental Cash Flow Information [Abstract]
Interest paid		$ 34,306	$ 29,526	$ 25,957
Income taxes paid (receipts), net	[1]	(13,102)	9,800	3,166
Accrued capital expenditures		22,734	17,247	5,970
Cash, Cash Equivalents, And Restricted Cash [Abstract]
Cash and cash equivalents		21,302	11,140
Restricted cash		1,113	858
Receivable - margin account		2,081	3,028
Cash, cash equivalents, and restricted cash		24,496	15,026	17,968	$ 18,835
MGE [Member]
Supplemental Cash Flow Information [Abstract]
Interest paid	[2]	34,306	29,526	25,957
Income taxes paid (receipts), net	[1],[2]	(16,208)	9,440	1,480
Accrued capital expenditures	[2]	22,734	17,247	5,970
Cash, Cash Equivalents, And Restricted Cash [Abstract]
Cash and cash equivalents		16,865	2,819
Restricted cash		1,113	858
Receivable - margin account		2,081	3,028
Cash, cash equivalents, and restricted cash		$ 20,059	$ 6,705	$ 10,500	$ 7,798

[1] Cash received for income taxes in 2024 includes $18.5 million related to PTCs generated in 2023 and 2024 that were sold to a third party.

[2] MGE Energy files a consolidated federal income tax return with its subsidiaries. While taxes are filed on a consolidated basis, MGE calculates its respective share of tax liability and makes intercompany tax payments to or from its parent company.