Commitments and Contingencies (Details-2) $ in Thousands	Dec. 31, 2025 USD ($)
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	$ 91,181
Purchase obligation due in second year	76,450
Purchase obligation due in third year	72,867
Purchase obligation due in fourth year	63,476
Purchase obligation due in fifth year	63,440
Purchase obligation due thereafter	350,537
Coal [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	15,564	[1]
Purchase obligation due in second year	8,207	[1]
Purchase obligation due in third year	6,349	[1]
Purchase obligation due in fourth year	0	[1]
Purchase obligation due in fifth year	0	[1]
Purchase obligation due thereafter	0	[1]
Natural Gas [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	52,875	[2]
Purchase obligation due in second year	56,266	[2]
Purchase obligation due in third year	61,430	[2]
Purchase obligation due in fourth year	61,249	[2]
Purchase obligation due in fifth year	61,199	[2]
Purchase obligation due thereafter	312,947	[2]
Purchased Power [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	5,980	[3]
Purchase obligation due in second year	5,795	[3]
Purchase obligation due in third year	258	[3]
Purchase obligation due in fourth year	0	[3]
Purchase obligation due in fifth year	0	[3]
Purchase obligation due thereafter	0	[3]
Renewable energy [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	7,369	[4]
Purchase obligation due in second year	3,403	[4]
Purchase obligation due in third year	3,434	[4]
Purchase obligation due in fourth year	1,385	[4]
Purchase obligation due in fifth year	1,413	[4]
Purchase obligation due thereafter	36,370	[4]
Other [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	9,393
Purchase obligation due in second year	2,779
Purchase obligation due in third year	1,396
Purchase obligation due in fourth year	842
Purchase obligation due in fifth year	828
Purchase obligation due thereafter	$ 1,220

[1] Total coal commitments for MGE's share of the Columbia and Elm Road Units, including transportation. Fuel procurement for MGE's jointly owned Columbia and Elm Road Units is handled by WPL and WEPCO, respectively, who are the operators of those facilities.

[2] MGE's natural gas transportation and storage contracts require fixed monthly payments for firm supply pipeline transportation and storage capacity. The pricing components of the fixed monthly payments for the transportation and storage contracts are approved by FERC but may be subject to change. MGE's natural gas supply commitments include market-based pricing.

[3] MGE has a purchase power agreement to help meet future electric supply requirements.

[4] Operational commitments for solar and wind facilities.