Commitments and Contingencies (Details-3) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014
Operating expense purchase contracts [Abstract]
Purchase obligation, 2014	$ 62,902
Purchase obligation, 2015	101,546
Purchase obligation, 2016	70,335
Purchase obligation, 2017	55,477
Purchase obligation, 2018	54,054
Coal [Member]
Operating expense purchase contracts [Abstract]
Purchase obligation, 2014	11,950	[1]
Purchase obligation, 2015	18,439	[1]
Purchase obligation, 2016	10,765	[1]
Purchase obligation, 2017	5,073	[1]
Purchase obligation, 2018	2,710	[1]
Natural Gas, Transportation and Storage [Member]
Operating expense purchase contracts [Abstract]
Purchase obligation, 2014	5,234	[2]
Purchase obligation, 2015	18,073	[2]
Purchase obligation, 2016	9,937	[2]
Purchase obligation, 2017	272	[2]
Purchase obligation, 2018	191	[2]
Natual Gas, Supply [Member]
Operating expense purchase contracts [Abstract]
Purchase obligation, 2014	16,951	[3]
Purchase obligation, 2015	16,070	[3]
Purchase obligation, 2016	0	[3]
Purchase obligation, 2017	0	[3]
Purchase obligation, 2018	0	[3]
Purchase Power [Member]
Operating expense purchase contracts [Abstract]
Purchase obligation, 2014	12,665	[4]
Purchase obligation, 2015	48,964	[4]
Purchase obligation, 2016	49,633	[4]
Purchase obligation, 2017	50,132	[4]
Purchase obligation, 2018	51,153	[4]
Other [Member]
Operating expense purchase contracts [Abstract]
Purchase obligation, 2014	16,102
Purchase obligation, 2015	0
Purchase obligation, 2016	0
Purchase obligation, 2017	0
Purchase obligation, 2018	$ 0

[1] Total coal commitments for the Columbia and Elm Road Units, including transportation. Fuel procurements for MGE's jointly owned Columbia and Elm Road Units are 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-based 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.