Taxes	6 Months Ended
Jun. 30, 2015
Income Tax Disclosure [Abstract]
Taxes	Taxes - MGE Energy and MGE. MGE Energy's effective income tax rates for the three and six months ended June 30, 2015, were 37.3% and 36.9%, respectively, compared to 39.1% and 37.7% for the same periods in 2014. MGE's effective income tax rates for the three and six months ended June 30, 2015, were 37.2% and 36.9%, respectively, compared to 39.1% and 37.7% for the same periods in 2014. The decrease in the effective tax rates is due in part to a higher domestic manufacturing deduction offset by lower AFUDC equity earnings in 2015.

Taxes

6 Months Ended

Jun. 30, 2015

Taxes - MGE Energy and MGE.

MGE Energy's effective income tax rates for the three and six months ended June 30, 2015, were 37.3% and 36.9%, respectively, compared to 39.1% and 37.7% for the same periods in 2014. MGE's effective income tax rates for the three and six months ended June 30, 2015, were 37.2% and 36.9%, respectively, compared to 39.1% and 37.7% for the same periods in 2014. The decrease in the effective tax rates is due in part to a higher domestic manufacturing deduction offset by lower AFUDC equity earnings in 2015.