Equity and Financing Arrangements	9 Months Ended
Sep. 30, 2025
Equity and Financing Arrangements Disclosure [Abstract]
Equity and Financing Arrangements	Equity and Financing Arrangements - MGE Energy. a. Common Stock. MGE Energy sells shares of its common stock through its Direct Stock Purchase and Dividend Reinvestment Plan (the Stock Plan). Those shares may be newly issued shares or shares that are purchased in the open market by an independent agent for participants in the Stock Plan. Effective May 2025, MGE Energy transitioned to utilizing open market purchases for all shares issued under the Stock Plan. Sales of newly issued shares under the Stock Plan are covered by a shelf registration statement that MGE Energy filed with the SEC. During the nine months ended September 30, 2025, MGE Energy issued approximately 40,995 shares of common stock under the Stock Plan. The net proceeds from these issuances were approximately $3.8 million, which were used for general corporate purposes. b. Dilutive Shares Calculation. As of September 30, 2025, 33,453 shares were included in the calculation of diluted earnings per share related to nonvested equity awards. See Footnote 7 for additional information on share-based compensation awards. c. Long-Term Debt Issuance - MGE Energy and MGE. On October 14, 2025, MGE entered into a private placement Note Purchase Agreement in which it committed to issue $25 million of 5.12% senior unsecured notes due 2036 and $25 million of 5.76% senior unsecured notes due 2055. Funding is expected to occur on November 13, 2025. The proceeds of the senior notes will be used to assist with capital expenditures and other corporate obligations. The covenants of these senior notes are substantially consistent with MGE's existing senior unsecured notes.

Equity and Financing Arrangements

9 Months Ended

Sep. 30, 2025

Equity and Financing Arrangements Disclosure [Abstract]

Equity and Financing Arrangements - MGE Energy.

Common Stock.

MGE Energy sells shares of its common stock through its Direct Stock Purchase and Dividend Reinvestment Plan (the Stock Plan). Those shares may be newly issued shares or shares that are purchased in the open market by an independent agent for participants in the Stock Plan. Effective May 2025, MGE Energy transitioned to utilizing open market purchases for all shares issued under the Stock Plan. Sales of newly issued shares under the Stock Plan are covered by a shelf registration statement that MGE Energy filed with the SEC. During the nine months ended September 30, 2025, MGE Energy issued approximately 40,995 shares of common stock under the Stock Plan. The net proceeds from these issuances were approximately $3.8 million, which were used for general corporate purposes.

Dilutive Shares Calculation.

As of September 30, 2025, 33,453 shares were included in the calculation of diluted earnings per share related to nonvested equity awards. See Footnote 7 for additional information on share-based compensation awards.

Long-Term Debt Issuance - MGE Energy and MGE.

On October 14, 2025, MGE entered into a private placement Note Purchase Agreement in which it committed to issue $25 million of 5.12% senior unsecured notes due 2036 and $25 million of 5.76% senior unsecured notes due 2055. Funding is expected to occur on November 13, 2025. The proceeds of the senior notes will be used to assist with capital expenditures and other corporate obligations. The covenants of these senior notes are substantially consistent with MGE's existing senior unsecured notes.