Taxes (Tables)

9 Months Ended

Sep. 30, 2018

Income Tax Disclosure [Abstract]

Effective Tax Rate Reconciliation

The consolidated income tax provision differs from the amount computed by applying the statutory federal income tax rate to income before income taxes, as follows:

	MGE Energy		MGE
Three Months Ended September 30,	2018	2017	2018	2017
Statutory federal income tax rate	21.0 %	35.0 %	21.0 %	35.0 %
State income taxes, net of federal benefit	6.3 %	5.2 %	6.2 %	5.1 %
Amortized investment tax credits	(0.1)%	(0.3)%	(0.1)%	(0.4)%
Credit for electricity from wind energy	(0.3)%	(1.1)%	(0.2)%	(1.1)%
Domestic manufacturing deduction	-%	(1.5)%	-%	(1.4)%
AFUDC equity, net	(0.6)%	(0.1)%	(0.6)%	(0.1)%
Amortization of utility excess deferred tax - tax reform(a)	(1.8)%	-%	(1.8)%	-%
Other, net, individually insignificant	-%	(0.3)%	0.1 %	(0.4)%
Effective income tax rate	24.5 %	36.9 %	24.6 %	36.7 %
	MGE Energy		MGE
Nine Months Ended September 30,	2018	2017	2018	2017
Statutory federal income tax rate	21.0 %	35.0 %	21.0 %	35.0 %
State income taxes, net of federal benefit	6.3 %	5.2 %	6.2 %	5.1 %
Amortized investment tax credits	(0.1)%	(0.3)%	(0.1)%	(0.4)%
Credit for electricity from wind energy	(0.3)%	(1.3)%	(0.3)%	(1.4)%
Domestic manufacturing deduction	-%	(1.6)%	-%	(1.7)%
AFUDC equity, net	(0.8)%	(0.2)%	(0.8)%	(0.2)%
Amortization of utility excess deferred tax - tax reform(a)	(1.8)%	-%	(2.0)%	-%
Other, net, individually insignificant	-%	(0.2)%	0.1 %	(0.1)%
Effective income tax rate	24.3 %	36.6 %	24.1 %	36.3 %

(a)Included are impacts of the Tax Act for the regulated utility for excess deferred taxes recognized using a normalization method of accounting.