Commitments and Contingencies (Details-1) $ in Thousands	Dec. 31, 2015 USD ($) MW
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	$ 144,987
Purchase obligation due in second year	80,787
Purchase obligation due in third year	78,397
Purchase obligation due in fourth year	56,578
Purchase obligation due in fifth year	48,137
Coal [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	38,028	[1]
Purchase obligation due in second year	13,115	[1]
Purchase obligation due in third year	12,736	[1]
Purchase obligation due in fourth year	3,850	[1]
Purchase obligation due in fifth year	0	[1]
Natural Gas, Transportation and Storage [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	18,500	[2]
Purchase obligation due in second year	18,551	[2]
Purchase obligation due in third year	18,482	[2]
Purchase obligation due in fourth year	17,562	[2]
Purchase obligation due in fifth year	14,254	[2]
Natural Gas, Supply [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	10,611	[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 Power [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	47,901	[4]
Purchase obligation due in second year	48,398	[4]
Purchase obligation due in third year	46,855	[4]
Purchase obligation due in fourth year	35,023	[4]
Purchase obligation due in fifth year	$ 33,883	[4]
Purchase Power Agreement, Osceola Windpower II, LLC [Member]
Purchase Power Agreement [Abstract]
Long-term purchase commitment, minimum power required (in MW) | MW	50
Other [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase obligation due in next twelve months	$ 29,947
Purchase obligation due in second year	723
Purchase obligation due in third year	324
Purchase obligation due in fourth year	143
Purchase obligation due in fifth year	$ 0

[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 . If any minimum purchase obligations must be paid under these contracts, management believes these obligations would be considered costs of service and recoverable in rates.

[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 established by FERC but may be subject to change.

[3] These commitments include market-bas ed pricing. Management expects to recover these costs in future customer rates.

[4] MGE has several purchase power agreements to help meet future electric supply requirements. Management expects to recover these costs in future customer rates. In October 2008, MGE entered into a purchase power agreement to help meet future electric supply requirements. Under this agreement, MGE has agreed to purchase 50 MW of wind power from Osceola Windpower II, LLC, which is located in I owa. This facility became operational in October 2008. MGE does not have any capacity payment commitments under this agreement. However, MGE is obligated to purchase its ratable share of the energy produced by the project. MGE's commitment related to its r atable share of energy produced by the project has been estimated and is included in the above numbers.