Taxes	3 Months Ended
Mar. 31, 2016
Income Tax Disclosure [Abstract]
Taxes	Taxes - MGE Energy and MGE. Effective Tax Rate. MGE Energy's effective income tax rate for the three months ended March 31, 2016 and 2015, was 36.9% and 36.7%, respectively. MGE's effective income tax rate for the three months ended March 31, 2016 and 2015, was 36.8% and 36.6%, respectively. The increase in the effective tax rate is due in part to a lower estimated domestic manufacturing deduction and lower estimated AFUDC equity earnings in 2016.

Taxes

3 Months Ended

Mar. 31, 2016

Taxes - MGE Energy and MGE.

Effective Tax Rate.

MGE Energy's effective income tax rate for the three months ended March 31, 2016 and 2015, was 36.9% and 36.7%, respectively. MGE's effective income tax rate for the three months ended March 31, 2016 and 2015, was 36.8% and 36.6%, respectively. The increase in the effective tax rate is due in part to a lower estimated domestic manufacturing deduction and lower estimated AFUDC equity earnings in 2016.