Pension and Other Postretirement Plans (Tables)

3 Months Ended

Mar. 31, 2014

Compensation and Retirement Disclosure [Abstract]

Schedule of Net Periodic Benefit Costs

The following table presents the components of MGE Energy's and MGE's net periodic benefit costs recognized for the three months endedMarch 31,2014 and 2013. A portion of the net periodic benefit cost is capitalized within the consolidated balance sheets.

		Three Months Ended
		March 31,
(In thousands)		2014		2013
Pension Benefits
Components of net periodic (benefit) cost:
Service cost	$	1,484	$	1,929
Interest cost		3,251		3,186
Expected return on assets		(5,279)		(4,776)
Amortization of:
Prior service (benefit) cost		49		79
Actuarial loss		173		2,015
Net periodic (benefit) cost	$	(322)	$	2,433
Postretirement Benefits
Components of net periodic (benefit) cost:
Service cost	$	330	$	596
Interest cost		772		970
Expected return on assets		(654)		(544)
Amortization of:
Transition obligation		1		1
Prior service (benefit) cost		(668)		28
Actuarial loss		39		311
Net periodic (benefit) cost	$	(180)	$	1,362