Taxes	9 Months Ended
Sep. 30, 2015
Income Tax Disclosure [Abstract]
Taxes	Taxes - MGE Energy and MGE. MGE Energy's effective income tax rates for the three and nine months ended September 30, 2015, were 35.1% and 36.1%, respectively, compared to 38.0% and 37.8% for the same periods in 2014. MGE's effective income tax rates for the three and nine months ended September 30, 2015, were 35.1% and 36.1%, respectively, compared to 37.9% and 37.8% 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

9 Months Ended

Sep. 30, 2015

Taxes - MGE Energy and MGE.

MGE Energy's effective income tax rates for the three and nine months ended September 30, 2015, were 35.1% and 36.1%, respectively, compared to 38.0% and 37.8% for the same periods in 2014. MGE's effective income tax rates for the three and nine months ended September 30, 2015, were 35.1% and 36.1%, respectively, compared to 37.9% and 37.8% 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.