Commitments and Contingencies (Details-2) $ in Thousands	Dec. 31, 2020 USD ($)
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	$ 79,290
Purchase obligation due in second year	47,674
Purchase obligation due in third year	32,880
Purchase obligation due in fourth year	29,546
Purchase obligation due in fifth year	29,000
Purchase obligation due thereafter	61,864
Coal [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	11,399	[1]
Purchase obligation due in second year	5,249	[1]
Purchase obligation due in third year	1,515	[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, Transportation and Storage [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	21,851	[2]
Purchase obligation due in second year	22,120	[2]
Purchase obligation due in third year	22,553	[2]
Purchase obligation due in fourth year	22,553	[2]
Purchase obligation due in fifth year	22,553	[2]
Purchase obligation due thereafter	18,316	[2]
Natural Gas, Supply [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	9,527	[3]
Purchase obligation due in second year	0	[3]
Purchase obligation due in third year	0	[3]
Purchase obligation due in fourth year	0	[3]
Purchase obligation due in fifth year	0	[3]
Purchase obligation due thereafter	0	[3]
Purchase Power [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	27,017	[4]
Purchase obligation due in second year	15,399	[4]
Purchase obligation due in third year	5,856	[4]
Purchase obligation due in fourth year	5,458	[4]
Purchase obligation due in fifth year	5,567	[4]
Purchase obligation due thereafter	11,717	[4]
Renewable energy
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	6,663	[5]
Purchase obligation due in second year	2,862	[5]
Purchase obligation due in third year	1,245	[5]
Purchase obligation due in fourth year	759	[5]
Purchase obligation due in fifth year	776	[5]
Purchase obligation due thereafter	30,939	[5]
Other [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	2,833
Purchase obligation due in second year	2,044
Purchase obligation due in third year	1,711
Purchase obligation due in fourth year	776
Purchase obligation due in fifth year	104
Purchase obligation due thereafter	$ 892

[1] Total coal commitments for 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.

[3] These commitments include market-based pricing.

[4] MGE has several purchase power agreements to help meet future electric supply requirements.

[5] Operational commitments for solar and wind facilities.